Archive for the ‘Female Genetics’ Category

Read: Hidden Figures and the appeal of math in an age of inequality

One name sprang readily to mind: Jennifer Smith. Huerta-Snchez remembered reading a classic, decades-old paper in which Smith was thanked in the acknowledgments for ably programming and executing all the computations. That seemed odd. Today, programming is recognized as crucial work, and if a scientist did all the programming for a study, she would expect to be listed as an author. It was weird to me that Smith was not an author on that paper, Huerta-Snchez says. [Rori and I] wanted to see if there were more women like her.

The duo recruited five undergraduate students, who looked at every issue of a single journalTheoretical Population Biologypublished between 1970 and 1990. They pored through hard copies of almost 900 papers, pulled out every name in the acknowledgments, worked out whether they did any programming, and deduced their genders where possible. Rochelle Reyes, one of the students, says that she was extremely motivated to do this work, having grown up on stories of under-recognized pioneers like Rosalind Franklin, who was pivotal in deciphering the structure of DNA, and Henrietta Lacks, whose cells revolutionized medical research. I was fortunate to grow up in a diverse environment with a passion for science as well as social justice, Reyes says.

She and her colleagues found that in the 1970s, women accounted for 59 percent of acknowledged programmers, but just 7 percent of actual authors. That decade was a pivotal time for the field of population genetics, when the foundations of much modern research were laid. Based on authorship at the time, it seems that this research was conducted by a relatively small number of independent individual scientists, nearly all of whom were men, the team writes. But that wasnt the case.

Its hard to know what sort of contributions people in the past have made behind the scenes, says Jessica Abbott, a geneticist at Lund University. But this study shows that its possible to get the right kind of data if you think creatively.

Margaret Wu, for example, was thanked in a 1975 paper for help with the numerical work, and in particular for computing table I. She helped to create a statistical tool that scientists like Huerta-Snchez still regularly use to estimate how much genetic diversity there should be in a population of a given size. That tool is called the Watterson estimator, after the 1975 papers one and only authorG. A. Watterson. The paper has since been cited 3,400 times.

Skeptics might argue that the programmers listed in these old papers were just doing menial work that wasnt actually worthy of authorship. Rohlfs says thats unlikely, especially in the cases of Wu, Jennifer Smith, and Barbara McCann, who were repeatedly name-checked in many papers. They were doing work that was good enough that they were being called back again and again, she says. The team even talked with William Hill, Smiths former supervisor at the University of Edinburgh, who described her work as both technical and creative. (He didnt, unfortunately, know where Smith ended up, and the team never managed to track her down.)

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Women's History in Science Is Hidden in the Footnotes ...

Here we have reversed the True Cannabliss cut of Head Seeds Casey Jones, now widely available on the Amsterdam coffee shop scene and we used it to pollinate itself. Casey Jones is a true elite strain in seed form and we are extremely grateful to Head Seeds for bringing it to the world. The spectrums of flavour we hope to represent with these S1s are a meaty/earthy funk with sweet fruity diesel undertones. We give all credit to grateful Head Seeds as all we did was remake his already outstanding work into fem seed Expect monster yields.

All our descriptions and images have come direct from the breeders who operate in a legal climate much different to that within the United Kingdom. Take note, you should NEVER try cultivating any cannabis plants within ANY jurisdiction where such cultivation is illegal. Our seeds are sold purely for souvenirs and should be treated as a curio or novelty item and should never be germinated. PLEASE DO NOT BREAK THE LAW!

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Grateful Casey Female Cannabis Seeds by Connoisseur Genetics

Heredity was for a long time one of the most puzzling and mysterious phenomena of nature. This was so because the sex cells, which form the bridge across which heredity must pass between the generations, are usually invisible to the naked eye. Only after the invention of the microscope early in the 17th century and the subsequent discovery of the sex cells could the essentials of heredity be grasped. Before that time, ancient Greek philosopher and scientist Aristotle (4th century bc) speculated that the relative contributions of the female and the male parents were very unequal; the female was thought to supply what he called the matter and the male the motion. The Institutes of Manu, composed in India between 100 and 300 ad, consider the role of the female like that of the field and of the male like that of the seed; new bodies are formed by the united operation of the seed and the field. In reality both parents transmit the heredity pattern equally, and, on average, children resemble their mothers as much as they do their fathers. Nevertheless, the female and male sex cells may be very different in size and structure; the mass of an egg cell is sometimes millions of times greater than that of a spermatozoon.

The ancient Babylonians knew that pollen from a male date palm tree must be applied to the pistils of a female tree to produce fruit. German botanist Rudolph Jacob Camerarius showed in 1694 that the same is true in corn (maize). Swedish botanist and explorer Carolus Linnaeus in 1760 and German botanist Josef Gottlieb Klreuter, in a series of works published from 1761 to 1798, described crosses of varieties and species of plants. They found that these hybrids were, on the whole, intermediate between the parents, although in some characteristics they might be closer to one parent and in others closer to the other parent. Klreuter compared the offspring of reciprocal crossesi.e., of crosses of variety A functioning as a female to variety B as a male and the reverse, variety B as a female to A as a male. The hybrid progenies of these reciprocal crosses were usually alike, indicating that, contrary to the belief of Aristotle, the hereditary endowment of the progeny was derived equally from the female and the male parents. Many more experiments on plant hybrids were made in the 1800s. These investigations also revealed that hybrids were usually intermediate between the parents. They incidentally recorded most of the facts that later led Gregor Mendel (see below) to formulate his celebrated rules and to found the theory of the gene. Apparently, none of Mendels predecessors saw the significance of the data that were being accumulated. The general intermediacy of hybrids seemed to agree best with the belief that heredity was transmitted from parents to offspring by blood, and this belief was accepted by most 19th-century biologists, including English naturalist Charles Darwin.

The blood theory of heredity, if this notion can be dignified with such a name, is really a part of the folklore antedating scientific biology. It is implicit in such popular phrases as half blood, new blood, and blue blood. It does not mean that heredity is actually transmitted through the red liquid in blood vessels; the essential point is the belief that a parent transmits to each child all its characteristics and that the hereditary endowment of a child is an alloy, a blend of the endowments of its parents, grandparents, and more-remote ancestors. This idea appeals to those who pride themselves on having a noble or remarkable blood line. It strikes a snag, however, when one observes that a child has some characteristics that are not present in either parent but are present in some other relatives or were present in more-remote ancestors. Even more often, one sees that brothers and sisters, though showing a family resemblance in some traits, are clearly different in others. How could the same parents transmit different bloods to each of their children?

Mendel disproved the blood theory. He showed (1) that heredity is transmitted through factors (now called genes) that do not blend but segregate, (2) that parents transmit only one-half of the genes they have to each child, and they transmit different sets of genes to different children, and (3) that, although brothers and sisters receive their heredities from the same parents, they do not receive the same heredities (an exception is identical twins). Mendel thus showed that, even if the eminence of some ancestor were entirely the reflection of his genes, it is quite likely that some of his descendants, especially the more remote ones, would not inherit these good genes at all. In sexually reproducing organisms, humans included, every individual has a unique hereditary endowment.

Lamarckisma school of thought named for the 19th-century pioneer French biologist and evolutionist Jean-Baptiste de Monet, chevalier de Lamarckassumed that characters acquired during an individuals life are inherited by his progeny, or, to put it in modern terms, that the modifications wrought by the environment in the phenotype are reflected in similar changes in the genotype. If this were so, the results of physical exercise would make exercise much easier or even dispensable in a persons offspring. Not only Lamarck but also other 19th-century biologists, including Darwin, accepted the inheritance of acquired traits. It was questioned by German biologist August Weismann, whose famous experiments in the late 1890s on the amputation of tails in generations of mice showed that such modification resulted neither in disappearance nor even in shortening of the tails of the descendants. Weismann concluded that the hereditary endowment of the organism, which he called the germ plasm, is wholly separate and is protected against the influences emanating from the rest of the body, called the somatoplasm, or soma. The germ plasmsomatoplasm are related to the genotypephenotype concepts, but they are not identical and should not be confused with them.

The noninheritance of acquired traits does not mean that the genes cannot be changed by environmental influences; X-rays and other mutagens certainly do change them, and the genotype of a population can be altered by selection. It simply means that what is acquired by parents in their physique and intellect is not inherited by their children. Related to these misconceptions are the beliefs in prepotencyi.e., that some individuals impress their heredities on their progenies more effectively than othersand in prenatal influences or maternal impressionsi.e., that the events experienced by a pregnant female are reflected in the constitution of the child to be born. How ancient these beliefs are is suggested in the Book of Genesis, in which Laban produced spotted or striped progeny in sheep by showing the pregnant ewes striped hazel rods. Another such belief is telegony, which goes back to Aristotle; it alleged that the heredity of an individual is influenced not only by his father but also by males with whom the female may have mated and who have caused previous pregnancies. Even Darwin, as late as 1868, seriously discussed an alleged case of telegony: that of a mare mated to a zebra and subsequently to an Arabian stallion, by whom the mare produced a foal with faint stripes on his legs. The simple explanation for this result is that such stripes occur naturally in some breeds of horses.

All these beliefs, from inheritance of acquired traits to telegony, must now be classed as superstitions. They do not stand up under experimental investigation and are incompatible with what is known about the mechanisms of heredity and about the remarkable and predictable properties of genetic materials. Nevertheless, some people still cling to these beliefs. Some animal breeders take telegony seriously and do not regard as purebred the individuals whose parents are admittedly pure but whose mothers had mated with males of other breeds. Soviet biologist and agronomist Trofim Denisovich Lysenko was able for close to a quarter of a century, roughly between 1938 and 1963, to make his special brand of Lamarckism the official creed in the Soviet Union and to suppress most of the teaching and research in orthodox genetics. He and his partisans published hundreds of articles and books allegedly proving their contentions, which effectively deny the achievements of biology for at least the preceding century. The Lysenkoists were officially discredited in 1964.

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heredity | Definition & Facts | Britannica.com

A variety of genetic and environmental factors likely play a role in causing androgenetic alopecia. Although researchers are studying risk factors that may contribute to this condition, most of these factors remain unknown. Researchers have determined that this form of hair loss is related to hormones called androgens, particularly an androgen called dihydrotestosterone. Androgens are important for normal male sexual development before birth and during puberty. Androgens also have other important functions in both males and females, such as regulating hair growth and sex drive.

Hair growth begins under the skin in structures called follicles. Each strand of hair normally grows for 2 to 6 years, goes into a resting phase for several months, and then falls out. The cycle starts over when the follicle begins growing a new hair. Increased levels of androgens in hair follicles can lead to a shorter cycle of hair growth and the growth of shorter and thinner strands of hair. Additionally, there is a delay in the growth of new hair to replace strands that are shed.

Although researchers suspect that several genes play a role in androgenetic alopecia, variations in only one gene, AR, have been confirmed in scientific studies. The AR gene provides instructions for making a protein called an androgen receptor. Androgen receptors allow the body to respond appropriately to dihydrotestosterone and other androgens. Studies suggest that variations in the AR gene lead to increased activity of androgen receptors in hair follicles. It remains unclear, however, how these genetic changes increase the risk of hair loss in men and women with androgenetic alopecia.

Researchers continue to investigate the connection between androgenetic alopecia and other medical conditions, such as coronary heart disease and prostate cancer in men and polycystic ovary syndrome in women. They believe that some of these disorders may be associated with elevated androgen levels, which may help explain why they tend to occur with androgen-related hair loss. Other hormonal, environmental, and genetic factors that have not been identified also may be involved.

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Androgenetic alopecia - Genetics Home Reference - NIH

Several genes are known to be associated with higher risk of Alzheimers disease (conversely, in some cases these genes have been found to protect against the disease). One of these genes is known as APOE.

APOE has three common forms:

APOE2, the least common gene, is believed to play a role in reducing the risk of Alzheimers diseaseAPOE4, more common than APOE2, is believed to increase the risk of Alzheimers diseaseAPOE3, the most common gene, has not been found to increase or decrease the risk of developing Alzheimers disease

Inheriting one of the APOE4 gene variants found in about 20% of the populationmay increase the chance of developing Alzheimers disease by a factor of four. Inheriting two of APOE4 variants (one from each parent) will increase the chance by a factor of 10. Additionally, a 2014 study found that women with the APOE4 gene were twice as likely to get Alzheimers disease than women who do not carry the gene; for men with the APOE4 gene the risk factor does not increase.

Known genetic factors such as this account for a small percentage of all Alzheimers disease cases, but current research supported by Cure Alzheimers Fund and others indicates that genetics have a far greater influence than was previously thought. Additional candidate genes are being discovered and studied to determine their possible role in the disease. The genes we do know about account for a large percentage of early-onset cases: The rare Presenilin 1 and Presenilin 2 genes, for example, virtually guarantee development of Early Onset Alzheimers disease.

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Female genetics - Women and Alzheimer's

Common baldness in women, also called female pattern alopecia, is genetically inherited and can come from either the mothers or fathers side of the family. Female alopecia most commonly presents in a diffuse pattern, where hair loss occurs over the entire scalp. Less commonly, women exhibit a patterned distribution where most of the thinning occurs on the front and top of the scalp with relative sparing of the back and sides.

The type of hair loss, diffuse or patterned, has important implications for treatment. Women with diffuse hair loss are generally best treated medically, whereas women with patterned hair loss may be good candidates for hair transplant surgery. Interestingly, patterned hair loss is the most common type seen in men and accounts for why a greater proportion of men are candidates for surgery compared to women.

In women who are genetically predisposed to hair loss, both diffuse and patterned distributions are caused by the actions of two enzymes: aromatase (which is found predominantly in women) and 5-a reductase (which is found in both women and men). Diffuse hair loss is most often hereditary, but it can also be caused by underlying medical conditions, medications, and other factors; therefore, a thorough medical evaluation is an important part of the management.

In the next sections, we will take a closer look at both the mechanisms of genetically induced female hair loss as well as the medical conditions and drugs that can cause diffuse hair loss in women.

As with hair loss in men, female genetic hair loss largely stems from a complex stew of genes, hormones, and age. However, in women, there are even more players. In addition to 5-a reductase, testosterone, and dihydrotestosterone (DHT); which are also found in mens hair loss; also present in women are the enzyme aromatase and the female hormones estrone and estradiol. So lets break down the process that leads to common hair loss in women.

In both men and women, 5-a reductase reacts with testosterone to produce DHT, the hormone responsible for the miniaturization (shrinking) and the gradual disappearance of affected hair follicles. This explains why both men and women lose their hair. But one of the reasons why women seldom have the conspicuous bald areas that men do is because women naturally have only half the amount of 5-a reductase compared to men.

Adding to this complexity, in women, the enzyme aromatase is responsible for the formation of the female hormones, estrone, and estradiol, counteract the action of DHT. Women have higher levels of aromatase than men, especially at the frontal hairline. It is this presence of aromatase which may help explain why hair loss in women looks so different than in men, particularly with respect to the preservation of the frontal hairline. It may also explain why women have a poor response to the drug finasteride (Propecia), a medication widely used to treat hair loss in men that works by blocking the formation of DHT.

The following is a schematic chart of how the female hormones estrone and estradiol are produced and their relationship to DHT:

Womens hair seems to be particularly sensitive to underlying medical conditions. Since systemic medical conditions often cause a diffuse type of hair loss pattern that can be confused with genetic balding, it is important that women with undiagnosed alopecia be properly evaluated by a doctor specializing in hair loss (i.e., a dermatologist).

Below is a list of medical conditions that can lead to a diffuse pattern of hair loss:

A relatively large number of drugs can cause telogen effluvium, a condition where hair is shifted into a resting stage and then several months later shed. Fortunately, this shedding is reversible if the medication is stopped, but the reaction can be confused with genetic female hair loss if not properly diagnosed. Chemotherapy and radiotherapy can cause a diffuse type of hair loss called anagen effluvium that can be very extensive. This hair loss is also reversible when the therapy is over, but the hair does not always return to its pre-treatment thickness.

Causes of Telogen Effluvium

Causes of Anagen Effluvium

A host of dermatologic conditions can cause localized hair loss in women. The pattern that they produce is usually quite different from the diffuse pattern of female genetic hair loss and is easily differentiated from it by an experienced dermatologist. Occasionally, the diagnosis is difficult to make and tests, such as a scalp biopsy are necessary.

Localized hair loss in women may be sub-divided into scarring and non-scarring types.

Non-Scarring Alopecias

Alopecia Areata is a genetic, auto-immune disease that typifies the non-scarring type. It manifests with the sudden onset of discrete, round patches of hair loss associated with normal underlying skin. It usually responds quite well to local injections of corticosteroids.

Localized hair loss can be also be caused by constant pulling on scalp hair, either through braiding, tight clips or hair systems. Traction alopecia, the medical term for this condition, often causes reversible thinning but, if the tugging on the follicles persists for an extended period of time, the hair loss can be permanent. The most common presentation is thinning, or complete hair loss, at the frontal hairline and in the temples of women who wear their hair pulled tightly back. Early traction alopecia can reverse itself by simply wearing the hair loose. A hair transplant may be needed to restore the hair that is permanently lost from sustained traction.

Scarring Alopecias

Scarring hair loss can be caused by a variety of medical or dermatologic conditions such as Discoid Lupus, Lichen Planus, and infections. It can also be caused by thermal burns or local radiation therapy. Face-lift surgery may result in permanent localized hair loss that can be particularly bothersome if it occurs at the frontal hairline or around the temples. Fortunately, localized hair loss from injury or from medical problems are often amenable to hair transplantation.

Many of the factors that cause the rate of loss to speed up or slow down are unknown, but we do know that with age, a persons total hair volume will decrease. This is referred to as senile alopecia. Even when there is no predisposition to genetic balding, hair across the entire scalp will thin over time resulting in the appearance of less density. The age at which these effects finally manifest themselves varies from one individual to another and is mainly related to a persons genetic makeup.

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Causes of Hair Loss in Women | Bernstein Medical

The coveted prize was awarded to a Scottish veterinarian, two scientists who championed an overlooked protein and a pioneering researcher who helped advance the careers of other women.

The Lasker Awards, which are among the nations most prestigious prizes in medicine, were awarded on Tuesday to a Scottish veterinarian who developed the drug propofol, two scientists who discovered the hidden influence of genetic packing material called histones and a researcher who in addition to doing groundbreaking work in RNA biology, paved the way for a new generation of female scientists.

The awards are given by the Albert and Mary Lasker Foundation and carry a prize of $250,000 for each of three categories. They are sometimes called the American Nobels because 87 of the Lasker recipients have gone on to win the Nobel Prize.

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He developed the drug propofol, now a widely used anesthetic that has transformed surgery.

Dr. Glen, the recipient of the Lasker-DeBakey Clinical Medical Research Award, is only the second veterinarian to win a Lasker in 73 years, according to the foundation.

A pharmaceutical career was an unlikely path for Dr. Glen, but the fact that he was interested in anesthesia was no surprise: for years, he had taught the subject to students at Glasgow Universitys veterinary school. I was anesthetizing dogs, cats, horses whatever animals came around, Dr. Glen said in an interview. Once he used anesthesia on a pelican to fix its beak.

When he arrived in the 1970s at ICI Pharmaceuticals, later acquired by AstraZeneca, Dr. Glen had turned his attention to humans and was on the hunt for a replacement for thiopentone, a widely used anesthetic that quickly put patients to sleep but often made them groggy afterward.

In lab tests on mice, he and his colleagues discovered that one of the companys existing compounds, propofol, seemed to work as well as thiopentone but wore off quickly, without the hangover effect of the earlier drug. Propofol was approved in 1986 in the United Kingdom and in the United States three years later.

The drug, known as the milk of amnesia because of its milky consistency, has since been used by hundreds of millions of patients and is credited with leading to the rapid expansion of outpatient surgery because patients recover so quickly.

In 2009, propofols reputation took a hit after Michael Jacksons personal physician, Dr. Conrad Murray, administered a lethal dose of the drug to the singer. Dr. Murray was convicted in 2011 on charges of involuntary manslaughter, and Dr. Glen said he followed the trial closely.

It was never intended to be used in that way, Dr. Glen said. But of the drugs broader success, he said, Im delighted that it has become so widely used.

She became a champion of women in her field and trained nearly 200 future scientists.

Dr. Steitz, the recipient of the Lasker-Koshland Award for Special Achievement in Medical Science, said winning the award is particularly significant because it signals how far she has come since her days as an undergraduate lab technician in the early 1960s.

When I started out being excited by science but seeing that there werent any women scientists I thought I had no prospects whatsoever, she said in an interview. The one thing that I really wanted was to have the respect of my peers for the scientific contributions I made, and for my participation in the scientific community.

More than four decades later, Dr. Steitz has her own lab at Yale University and her work has led to several breakthroughs in the understanding of RNA, a type of molecule that carries out many tasks in the cell, such as helping to read the information in our genes.

One of her biggest discoveries was particles made up of RNA molecules and proteins, known as small nuclear ribonucleoproteins, or snRNPs for short. Theyre scattered throughout cells and among other things, they help cut messenger RNA into pieces, some of which get pasted back together. This process, called splicing, is essential to the process of making proteins from genes. This discovery led to an entire new field of research in cell biology.

She was an author of a 2007 National Academy of Sciences report that recommended specific steps for maximizing the potential of women in academic science and engineering. Since then, she gives talks about how to encourage more women in science and is also being recognized for her work as a mentor. She has trained almost 200 students and postdoctoral fellows, according to the Lasker foundation.

Of the 360 papers that have come from her laboratory, 60 do not include her name, a gesture of generosity that reflects her belief that students and postdoctoral fellows who work completely independently should be allowed to publish on their own, according to the Lasker foundations citation.

In an interview, Dr. Steitz downplayed this detail. She said in her early days running her own lab, she frequently left her name off papers because she was following in the scientific tradition she had learned as a young researcher.

As for her role as an activist, I sort of feel a little embarrassed by that, because there are so many women that have done so much more, she said. What she has done, she said is to be a good citizen and try to help women and other underrepresented people to fulfill their potential.

They took a new look at a protein once considered the packing material of DNA.

From opposite ends of the country, Dr. Allis, whose lab is at The Rockefeller University in New York, and Dr. Grunstein, at the University of California, Los Angeles, pioneered work that elevated the importance of histones, proteins in the chromosomes that previously had gone overlooked. They are the recipients of the Albert Lasker Basic Medical Research Award.

DNA molecules are so long that, if they were stretched from end to end, one strand would reach six feet. Histones are the proteins that coil and cram these strands into a microscopic cell and they were long seen as little more than DNA spools, part of the basic machinery of the cell.

I went into the field thinking, everyones working on gene activity, I want to work on packing material, Dr. Grunstein said in a video produced by the Lasker foundation. I didnt want to go the direction everyone else was going in.

What Dr. Grunstein and Dr. Allis discovered is that, in fact, histones play a crucial role in turning genes on and off, which allows each cell to do its assigned task. The two worked separately, Dr. Grunstein focusing on genetics, and Dr. Allis on biochemical processes.

While their award is for basic science, the practical implications for their discoveries are profound. Mistakes in setting this up seem to be very clearly causing cancer, Dr. Allis said in the video.

Drug developers used the evolving understanding of histones to come up with new treatments, including to treat cancer, such as Zolinza, sold by Merck. More are in the pipeline.

Its spawned really a whole new area of potential therapies in humans, and thats pretty rewarding, Dr. Allis said.

More coverage of the Lasker Awards

Katie Thomas covers the business of health care, with a focus on the drug industry. She started at The Times in 2008 as a sports reporter. @katie_thomas

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Lasker Awards Given for Work in Genetics, Anesthesia and ...

Melissa Franklin Professor of Physics, Harvard University "I build things, and then I fix them when I build them badly," says the experimental physicist, offering a deceptively modest description of her work. The objects she tinkers with are complex particle detectors, including the powerful proton-antiproton Collider Detector at Fermilab in Batavia, Illinois, which she used to spot the top quark in 1995.

Maria Zuber Professor of Geophysics and Planetary Science, MIT Using laser ranging, gravity measurements, and data from spacecraft, Zuber maps surface features and probes the interior of Mars, Venus, Jupiter's moons, and our own moon. Her goal is to "figure out the processes that acted on a particular body in the past in order to make its surface the way it is now."

Fame Passed Them By

History has not always been kind to women scientists. Many have passed long days and nights in the lab stirring noxious concoctions or gathering piles of data only to see the credit for their discoveries awarded to a male colleague. Sometimes the work was obscured by a famous mentor. Here is a selection of female scientists who deserve greater notice:

Lise Meitner (1878-1968) In 1938, after she escaped from the Nazis to Sweden, she carried out the key calculations that led to the discovery of nuclear fission. Her collaborator, Otto Hahn, who stayed behind in Germany, was the sole recipient of the Nobel Prize in chemistry in 1944. In 1997 Meitner was finally honored when element 109 was named meitnerium.

Emmy Noether (1882-1935) She devised a mathematical principle, called Noether's theorem, which became a foundation stone of quantum physics. Her calculations helped Einstein formulate his general theory of relativity. "It is really through her that I have become competent in the subject," he admitted.

Frieda Robscheit-Robbins (1893-1973) Together with George Whipple, she discovered that a diet rich in liver cured anemia in dogs, which in turn led directly to treatment for pernicious anemia in humans. Although she coauthored numerous papers with Whipple, it was he who was honored with the 1934 Nobel Prize in medicine.

Hilde Mangold (1898-1924) Under the guidance of Hans Spemann, she carried out the experiments that led to the discovery of the organizer effect, which directs the development of embryonic cells into tissues and organs. She died after being set afire by an alcohol stove on which she was heating food for her baby. Eleven years later, Spemann won the Nobel Prize.

Cecilia Payne-Gaposchkin (1900-1979) In her 1925 Ph.D. thesisdescribed by the noted astronomer Otto Struve in 1960 as "the most brilliant . . . ever written in astronomy"she proposed that all stars are made mostly of hydrogen and helium. Astronomers dismissed her observations until four years later, when they were confirmed by a man. She was the first woman to become a professor of science at Harvard.

Beatrice "Tilly" Shilling (1909-1990) A prize-winning motorcycle racer and aeronautical engineer, she designed a small metal ring that fit onto the fuel line of an aircraft engine to keep the flow of fuel constant. This enabled World War II British fighter pilots to dive without fear that their engines would cut out.

Chien-Shiung Wu (1912-1997) In 1957 she and her colleagues overthrew a principle previously considered immutable in physics: that nature does not distinguish between right and left. Chien-Shiung found that this rule does not hold true for interactions between subatomic particles involving the so-called weak force. The Nobel Prize was awarded to two male colleagues.

Rosalind Franklin (1920-1958) Her X-ray photographs of crystallized DNA, taken in the early 1950s, proved that the molecule was a helix. This data was used, without her knowledge, by James Watson and Francis Crick to elucidate the structure of DNA. By the time they were awarded the Nobel Prize in 1962, Franklin had died of ovarian cancer.

Jocelyn Bell Burnell (1943-) With the aid of a radio telescope she built herself, she became the first astronomer to detect pulsarsrapidly spinning, extremely dense neutron stars. But she was deemed too inexperienced to receive the Nobel Prize, which was given instead in 1974 to her thesis adviser, Anthony Hewisha man who later referred to her as "a jolly good girl [who] was just doing her job."

Josie Glausiusz

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The 50 Most Important Women in Science - Discover Magazine

The key stages of female hormones and how hormonal imbalance affects your body.

Index:

You inhabit an amazing body that performs a myriad of functions every second of the day. This incredible feat is controlled by your brain and co-ordinated by your hormones. Millions of women are affected by hormonal changes throughout their lives but have little idea about how or why. Hormonal imbalances can lead to:

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Hormones are essentially chemical messengers secreted by endocrine glands in the body that are designed to adjust metabolic functions in cells. They do this by regulating the production of a specific protein or by activating enzymes.

There are two basic types of hormones, steroid and peptide. They travel to their target organs in the bloodstream and work in complicated harmony to maintain balance at all times. Steroid hormones are fat soluble compounds that can easily pass through cell membranes.

Some of these include:

Peptide hormones are water soluble compounds that are able to dissolve in the blood in order to be transported around the body. Some of these include:

Hormones are secreted by the endocrine system which is largely controlled by the pituitary gland - in the brain - under the direction of the hypothalamus.

Hormone balance (Homeostasis) is maintained by a key regulatory mechanism called negative feedback which either opposes the release of certain hormones or causes hormones to act antagonistically by opposing each others actions.

For example if blood sugar (glucose) levels are too high the brain sends a signal to release insulin which lowers blood glucose. If blood glucose levels drop too low the brain triggers the release of glucagon which raises blood sugar.

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Hormones co-ordinate many diverse areas including:

When the correct balance of hormones is maintained most daily challenges are met and the body thrives, but if levels are too high or low it can lead to health problems such as thyroid disease, polycystic ovaries, endometriosis, infertility, fibroids, depression and acne.

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Female hormones exist primarily to promote growth and reproduction and have a significant effect on a womans development throughout her life. The two main female hormones, oestrogen and progesterone are produced predominantly in the ovaries but also in the adrenal glands which sit just above the kidneys.

At puberty oestrogen is responsible for the development and maturation of the uterus, fallopian tubes, breasts and vagina. It also plays a key role in the growth spurt and deposition of fat around the buttocks, hips and thighs.

There are at least six different oestrogens, however only three are synthesised in significant amounts:

Beta-estradiol, Estrone & Estriol.

Progesterone is involved in regulating the menstrual cycle and is vital for supporting a healthy pregnancy. It is also particularly important for balancing and controlling oestrogen performance, opposing some of the powerful effects of excess oestrogen. For instance oestrogen triggers release of the stress hormone cortisol while progesterone counters it.

Oestrogen stimulates cell growth, while progesterone ensures growth is maintained at healthy levels. Low progesterone levels lead to uncontrolled oestrogen which results in hormonal imbalances. Low levels of progesterone may affect:

Women also produce a little testosterone (normally considered a male hormone) from their ovaries, which helps to promote muscle mass and bone growth. These levels naturally decline post menopause.

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Puberty:

During this stage the ovaries are stimulated by luteinising hormone (LH) and follicle-stimulating hormone (FSH) which are secreted by the pituitary gland under the influence of the hypothalamus.

These hormones bring about the physical changes associated with puberty. Menstruation usually occurs around the time that a womans growth spurt slows down. The whole process takes around 4 years.

Pregnancy:

This is a time when a womans hormones change dramatically:

Menopause:

The lead up to the menopause (the peri-menopause) starts around the age of 40 and ends on average at age 52. Whilst there are considerable hormonal changes that occur during puberty and the childbearing years - the menopause and post menopause seem to be the most problematic. This life stage can be extremely challenging for some women.

Oestrogen plays a vital role in protecting the heart, bones, bladder and vagina as well as maintaining the breasts. Lack of oestrogen and progesterone during the menopause can create hormonal imbalances which have significant consequences for health with an increased risk of osteoporosis and heart disease and can also result in a range of distressing symptoms.

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The ratio between oestrogen and progesterone is critical for the maintenance of homeostasis. Often the effects of high oestrogen are due to a combination of mildly high oestrogen levels together with a mild progesterone deficiency.

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An increase in the ratio of oestrogen to progesterone can lead to:

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Hormone function can be disrupted if too much of a hormone is produced or too little. This may be due to a number of factors including:

Malnutrition

Undereating, a poor diet, insufficient calories and nutrients, reliance on stimulants and junk food can lead to a nutrient deficiency which will ultimately affect hormone production. For example, Studies have found that B6 supplementation has positive effects on some PMS symptoms. It is likely that B6 helps to balance oestrogen and progesterone levels mid cycle. B6 is also a co-factor in the synthesis of serotonin.

Being underweight with insufficient fat reduces cholesterol which is needed to produce sex and stress hormones. During the menopause oestrogen is produced in the abdominal fat cells as ovarian function diminishes.

Poor liver function

Oestrogen has to be metabolised by the liver and excreted in bile. If the liver is not functioning efficiently oestrogen levels in the blood may remain relatively high.

Overloading the liver with alcohol, drugs, caffeine and chemicals in food may lead to poor liver function.

Certain Foods

Too much sugar, alcohol, chocolate, fried foods, trans fats and refined carbohydrates can affect liver function which could contribute to higher oestrogen levels.

Constipation

Before used oestrogen can be eliminated via the stool it has to be modified by intestinal bacteria and bound to fibre. This bulks out the stool and encourages normal bowel movements.

Good levels of healthy gut bacteria and plenty of dietary fibre are essential for this process otherwise the used oestrogen may be recirculated.

Chemicals in food

Certain chemicals such as pesticide residues found in non-organic dairy and meat products can mimic oestrogens in the body.

Oestrogens are also included in cattle feed to fatten them up.

Environmental factors and xenoestrogens

There are many petrochemical products that affect the balance of hormones in the body. These include:

Alkylphenol ethoxylates in detergents and emulsifiers; nonylphenol ethoxylates used as spermicides and plasticisers; bisphenols used in certain industrial and chemical processes and dental fillings, the birth control pill and HRT

Genetics

There may be a family history of early menopause or low thyroid function.

Read more:
12 Female Hormones Facts - Understanding your Hormones Today

WHAT IS THE LIFE CYCLE OF HAIR

The average person is born with 100,000 hair follicles on their head, which are in a constant state of change. When a follicle is first activated, it grows thick hairs for several years. When the growth cycle is complete, the follicle undergoes a transitional phase before entering into a resting period where the hair is eventually shed, and the cycle begins again.

Hereditary hair loss starts with a progressive shortening of the hairs growth cycle and involves gradually shrinking hair follicles that eventually are no longer able to produce normal hair.

DIFFERENT TYPES OF HAIR LOSS

Hair thinning is surprisingly common. More than 1 out of every 4 women will experience it at one time or another. While certain lifestyle factors can absolutely have an impact on your hairs thickness, over 90% of all hair loss is due to genetic factors. So before you start blaming your diet or blow dryer, get to know the facts behind the science of genetic hair thinning.

NOT ALL HAIR LOSS IS CREATED EQUAL

In general, hair loss falls into one of 2 categories: hereditary and non-hereditary. Hereditary hair loss is known as androgenetic alopecia (AGA) and is a genetic condition that shortens the time that the hair spends actively growing. AGA eventually causes the hair follicles to slowly shrink. Women with hereditary hair loss experience a general thinning of the hair, with the most extensive hair loss occurring on the top of the head and along the part. The number of women with this type of hair loss increases with age, but it can start as early as your 20s. Womens ROGAINE Foam is only indicated to treat hereditary hair loss.

On the flipside, temporary hair loss, known as telogen effluvium, happens when stress, diet, a hormonal imbalance, or a traumatic event causes the hair follicles to remain in the resting state, causing increased hair shedding and a temporary thinning of hair across the whole scalp. While the amount of time someone stays in telogen effluvium varies, once the imbalance has been corrected, the hair will return to its previous thickness.

A third kind of hair loss is called alopecia areata, an autoimmune disorder that is recognized by well-defined patches of hair loss, which may happen rapidly and can lead to complete hair loss. If you have no history of hair loss in your family and are experiencing this kind of hair loss, consult your doctor.

If youre not certain about what kind of hair thinning youre experiencing, our quizcan help you start to sort things out.

WHOS TO BLAME? MOM OR DAD?

Its a commonly held myth that genetic hair loss is only inherited from one side of the family or the other. In reality, you can inherit the thinning hair gene from either your mother or father (or both). That being said, if a number of close relatives have thinning hair, your chances of experiencing it increase, but are by no means inevitable.

NOT JUST FOR MEN

Incorrectly thought of as only a male ailment, both men and women experience hair loss, but in varying patterns and severity. Men will tend to recede at the hair line and/or experience hair loss around the crown of the head, whereas a womans hair loss usually involves a more dispersed thinning on the top of the head, which may be especially noticeable as a widening part.

More here:
Genetic Reasons: Female Hair Loss | Women's ROGAINE

In fact, by focusing only on common ancestry of DNA that gets inherited,all CA's found in genetic studies will be much older than the MRCA.

Our most recent female-female line ancestor is called "Mitochondrial Eve"since Mitochondrial DNA passes (almost) entirely through the female lineand so may be used to estimate a date for her.Contrary to a lot of confused discussion,e.g. [Ayala, 1995],Mitochondrial Eve's existence is not in doubt.We can work it out from our armchair.What is in dispute is the date,which has been estimated at 100,000 to 200,000 years ago.

Also contrary to much confused discussion by paleontologists,no date for Mitochondrial Eve implies any sort ofpopulation bottleneck at that time. Mitochondrial Eve would have co-existedwith huge numbers of male andfemale relations from whom we also descend.Indeed, [Ayala, 1995] points out thatour inheritance from Mitochondrial Evewould be only 1 part in 400,000 of our DNA.The rest we inherit from her contemporaries.But he still spends half the paper attacking the ideaof a small ancestral population - an idea that no one believes.

As a result of thinking about Y chromosome Adam, we can see that if we use surnames strictly in the male line forever into the future,then not only will all hereditary titles die out,but all surnames except one will die out too.

The world does not of course strictly follow that surname rule,but the West approximately does,and surnames do go extinct.Without a mechanism for generating entirely new surnames from scratch(not belonging to either parent)the diversity of surnames can only decline.Neil Frasernicely describes it as"a random walk - next to a cliff. The only force acting on the system is that once a name randomly stumbles to zero it is gone and can never recover."

Say for one gene, your father's two copies are AB,your mother's are CD.You could end up with AC, your sibling could end up with BD.For this gene only,there is no genetic evidence of your recent common ancestry.

If there are n events at which to choose betweenyour father's grandfather copy and grandmother copy,the probability of you inheriting from himnone of your grandfather's DNA (*)is:

(*) If you are your father's daughter.If his son, you must inherit the Y chromosome.We will ignore the special cases of themale-male and female-female lines.Admittedly these are hard to ignore with grandparents,since they are 2 of only 4 lines,but these 2 special lines can be ignored as we go back 10 generations or more.

[Chang, 1999, author's reply]discusses this extreme case.I'm not sure if n=23 here(the no. of chromosomes).Then the probability of all grandmother,none from grandfather, would be(1/2)23= 1 in 223= 1 in 8.4 million.

If we allow for crossover, the probability of all grandmother,none from grandfather, is:

If n=23,(1/4)23= 1 in 246= 1 in 70 trillion.

Q. Is n=23?

If n=23probability (3/4)23 = 1 in 747.

How does crossover affect this?If one great-grandparent is c,your father has 3/4 chance of getting either c,or c crossed with d.He then has 3/4 chance of passing this on,either as is or crossed over.So you have (3/4)2 = 0.56 chance of inheriting some c,or 1 - (3/4)2 = 0.44 chance of inheriting none.So we get chance of inheriting no DNAfrom a great-grandparent is:

If n=23probability (0.44)23= 1 in 181 million.

Q. Is n=23?

If n=23, the probability depends on t.This is equal to 1/2 for:1-(1/2)t-1 = 0.971/2t-1 = 0.032t-1 = 33.7t-1 = 5In other words, more than 6 generations back,the prob. of inheriting no DNA at all from one of yourancestors is more than 1/2.

But what about crossover?With crossover, the probability of inheriting none of the DNAof an ancestor at generation t is:

If n=23, the probability depends on t.This is equal to 1/2 for:(3/4)t-1 = 0.03t-1 = 12In other words, more than 13 generations back,the prob. of inheriting no DNA at all from one of yourancestors is more than 1/2.Note that at 13 generations back (c. 1500s - 1600s) you have8192 ancestors.

Q. Is n=23?

For small n, it is easier (more probable) to not inherit from an ancestor.With a single event (n=1), it could easily lose that event.With a large number of events, it is unlikely it losesthem all.For large n, it is harder to not inheritfrom an ancestor.As n goes to infinity, you must have inherited some DNAfrom the ancestor.

We can see that above, for any finite t,as n goes to infinity,the probability of not inheriting goes to zero.

For an MRCA 30 generations ago,you need 230 people = 1 billion peopleto be sure that their samples of1 part in 230 of the ancestor's DNAmust overlap.

As I say, I need to do more reading on this.I'm sure this has been discussed before.There is some discussion of this in[Wiuf and Hein, 1999].

So the "real" CAs (the CA1s) outnumber the CAs of a gene (the CA4s),but do they vastly outnumber them?As genome size tends to infinity(i.e. n goes to infinity)it becomes impossible for an actual ancestor (CA1) not to be at leasta partial genetic ancestor (CA2) as well.So the difference between CA1 and CA2 breaks down.

I used to say on this page:

but now we can see this is not so.(At least I put in "(I think)" in the correct place!)The difference between CA2 and CA3 does not break down.For any finite n, you are getting a larger inheritance from the ancestoralright,but it is still only 1 part in 2t,so for any 2 descendants it is quite possible that their samplesdo not overlap (for any reasonable size t).The probability of overlap depends on t, not on n.

For instance, [O'Connell, 1995] is confused about Mitochondrial Eve's relation to the fossil record- no date for Mitochondrial Eve, no matter how recent,could possibly contradict the fossil record studied by the paleontologists.This is based on the error of assuming that Mitochondrial Eve is important(see above).

One could even say that genealogy is the pursuit of statistical artefacts.

Link:
Common ancestors of all humans (using genetics)

A wiring diagram of a human brain.Illustration: NIH

There may not be a single depression gene, but theres no question that our genetic makeup is an important factor in whether or not we get depressed. And our sex, it turns out, can be a factor in how those genes are expressed. In men and women diagnosed with major depressive disorder, the same genes show the opposite changes. In other words, the molecular underpinnings of depression in men and women may be different.

Thats according to a new postmortem brain study published on Wednesday in the journal Biological Psychiatry. The study could in the future help lead to more effective treatments for depression, if it turns out that men and women need different types of treatment.

To arrive at that conclusion, researchers at the University of Pittsburgh and Torontos Centre for Addiction and Mental Health analyzed gene expression levels in the postmortem brain tissue of 50 people who had major depressive disorder, of which 26 were men and 24 were women. (The data on their subjects was collected from several existing published data sets.) They also looked at the postmortem brain tissue of 50 men and women not diagnosed with depression. Gene expression levels are an indication of how much of a particular protein an individual gene is producing.

In the women with depression, they found that genes affecting synapse function were more expressed, meaning genes that play a role in how electrical activity is transferred between cells were producing more protein. In men, those same genes had decreased expression. In other genes with altered expression, a particular change occurred in only men or only women. Of 706 gene variants in men with depression and 882 variants in women with depression, 52 of the genes showed opposite changes in expression between the men and women. Only 21 genes changed in the same way in both sexes.

In the study, researchers focused on three regions of the brain that regulate mood: the dorsolateral prefrontal cortex, subgenual anterior cingulate cortex, and basolateral amygdala. To bolster their findings, they also looked at a smaller dataset of men and women with major depressive disorder and found similar results. More research, including studies in living patients, will be necessary to further validate the results.

The study is significant for two reasons. For one, it is the first to suggest an opposing pathology for depression in men and women, which could eventually influence how depression is treated. Depression is complex disease that occurs in different regions of the brain, and increased understanding of the neurology and genetics of depression may lead to tailored depression treatments that are far more effective.

But the study also highlights the necessity of diversity in scientific study. Major depressive disorder affects women about twice as often as men. Women are also more likely to experience symptoms like weight gain along with depression, suggesting the biological mechanisms at work may be different. But many depression studies only look at men, and ones that look at both sexes do not necessarily differentiate between the two when reporting findings.

The science of genetics overwhelmingly suggests how similar we all really are. But it also underscores how much there is to gain from understanding and embracing how we are different.

Visit link:
The Genetics of Depression Are Different for Men and Women

Many women are unable to conceive and deliver a healthy baby due to genetic factors. Sometimes this is due to an inherited chromosome abnormality. Other times it is because of a single-gene defect passed from parent to child.

In addition, if other women in your family have had problems conceiving due to premature menopause, endometriosis or other factors, you may be at increased risk of the same problems.

Chromosomally abnormal embryos have a low rate of implantation in the mothers uterus, often leading to miscarriages. If an abnormal embryo does implant, the pregnancy may still result in miscarriage or the birth of a baby with physical problems, developmental delay, or mental retardation.

There are several kinds of chromosome abnormalities:

Translocation is the most common of these. Although a parent who carries a translocation is frequently normal, his or her embryo may receive too much or too little genetic material, and a miscarriage often results.

Couples with specific chromosome defects may benefit from pre-implantation genetic diagnosis (PGD) in conjunction with in vitro fertilization (IVF).

Down syndrome is usually associated with advanced maternal age and is a common example of aneuploidy. Down syndrome is caused by having an extra number-21 chromosome (three instead of two). It is also referred to as trisomy 21.

More rare is the existence of an inherited genetic disease due to abnormal genes or mutations. Chromosome analysis of the parents blood identifies such an inherited genetic cause in less than 5 percent of couples.

Single-gene abnormalities are mutations caused by changes in the DNA sequence of a gene, which produce proteins that allow cells to work properly. Gene mutations alter the functioning of cells due to a lack of a protein.

Single-gene disorders usually indicate a family history of a specific genetic disease such as cystic fibrosis (CF) an incurable and fatal disease affecting the mucous glands of vital organs and Tay Sachs, also a fatal disorder, in which harmful quantities of a fatty substance build up in tissues and nerve cells in the brain.

Though generally rare, these diseases are usually devastating to a family. Fortunately, much progress has been made in detection through pre-implantation genetic diagnosis (PGD) in conjunction with in vitro fertilization (IVF).

Although a couple may otherwise have no fertility problems, IVF and PGD can work together to spare mother and father from heartache in cases where there is a known single-gene family history.

Learn more about genetic causes of infertility

Read this article:
Is Infertility Genetic? | Female Infertility Genetic ...

-A curious adult

June 25, 2014

That is a very interesting question! And one that many people wonder about. In fact, we answered a very similar question many years ago.

Twin genetics depend on what kind of twins we are talking about. Having identical twins is not genetic. On the other hand, fraternal twins can run in families.

Genetics can definitely play a role in having fraternal twins. For example, a woman that has a sibling that is a fraternal twin is 2.5 times more likely to have twins than average!

However, for a given pregnancy, only the mothers genetics matter. Fraternal twins happen when two eggs are simultaneously fertilized instead of just one. A fathers genes cant make a woman release two eggs.

It sounds like fraternal twins do indeed run in your family! But, since your son is the father, his genes are on the wrong side of the family tree. So, your family history likely didnt play a role in his wifes twin pregnancy.

The answer would be different if you were asking about a daughter. Also, although your sons family history of twins cant increase his wifes chance of having twins, he can pass those genes down to your granddaughter. With your strong family history of fraternal twins, this just might increase the chances of your granddaughter having twins!

But, your daughter-in-law is not necessarily having twins because of her genetics. Other things like environment, nutrition, age, and weight have also been linked to having twins as well. And there is always simple chanceevery woman has a chance at having fraternal twins. It is just that some women have a higher or lower chance.

Huh? Help Me Understand the Genetics!

Wait a minute. One type of twins has a genetic basis and the other does not? And, only the moms genetics matter? How is that possible?

Dont worry. It makes a lot of sense once we break down the biology.

The important difference between identical and fraternal twins is the number of fertilized eggs involved. Identical twins come from a single fertilized egg. Fraternal twins come from two different ones.

Identical twins happen when a single embryo splits in two soon after fertilization. This is why identical twins have identical DNA. They came from the same fertilized egg.

Since embryo splitting is a random event that happens by chance, it doesnt run in families. Genes are not involved. The same is not true for fraternal twins.

Fraternal twins happen when two independent eggs are each fertilized by different sperm. This is why the DNA of fraternal twins is different. In fact, fhe DNA of fraternal twins is no more similar than the DNA any other sibling pair.

Usually, a woman only releases a single egg at a time. Fraternal twins can only happen if a mother releases two eggs in one cycle. This is called hyperovulation.

Unlike embryo splitting, ovulation is a normal biological process that is controlled by our genes. And, different women can have different versions of these ovulation genes.

Some women have versions (called alleles) of these genes that make them more likely to hyperovulate. This means there is a higher chance that two eggs could get fertilized at once, leading to fraternal twins.

The gene versions that increase the chance of hyperovulation can be passed down from parent to child. This is why fraternal twins run in families.

However, only women ovulate. So, the mothers genes control this and the fathers dont.

This is why having a background of twins in the family matters only if it is on the mothers side. And why your sons family genetics did not play a role in his twins.

We went over a lot of this stuff in our previous answer, but your question got me thinking. Our last answer on twins was done so long ago. Has recent research discovered anything new on this fascinating topic? They have indeed at least if you are a sheep!

Counting Sheep can Teach us about Twins

Scientists often turn to animals when they want to study a biological process. Some of the newest information we have about twin genetics comes from studying sheep.

Sheep were chosen because, like people, they typically give birth to a single lamb. However, they can sometimes have twins and triplets.

Different breeds of sheep naturally have higher or lower twin rates. These different breeds have different versions (called alleles) of some of their genes. Specific alleles can make certain breeds more likely to have twins.

We can compare the genes between these different breeds to try to find the genes controlling twinning. And, this is just what scientists did.

A thorough search for genes controlling twining in sheep identified several interesting ones. The breeds with higher twin rates had different alleles of these genes!

Three key sheep genes identified were named BMP15, GDF9, and BMPR1B. The specific gene names are not really important. Just know that all of these genes are involved in controlling ovulation. Which makes sense!

Remember, hyperovulation increases the chance of having fraternal twins. The sheep breeds with higher than average twin rates had versions of the genes that increase ovulation.

Sheep are a great tool to help us study twin genetics. The tricky part is connecting these findings to people.

It is harder to study humans. Scientists have tried to find links between the genes identified in sheep and human twin genetics. So far theyve found that some match up and some dont. This, in and of itself, is interesting!

Another gene called follicle-stimulating hormone, or FSH for short, has also been linked to twins in humans. Like the other three genes identified, this FSH is also involved in promoting ovulation, and mothers of fraternal twins often have high levels of it.

It seems that twin genetics is more complicated in humans than in sheep. More genes are likely involved. But, each new bit of information about the genes involved adds another puzzle piece to the complete genetic picture.

Maybe someday we will know all the genes that cause fraternal twins in people. But for now, you can just tell your son that his genetics likely didnt cause his twins. Scientists are still trying to figure out which, if any, genes on his wifes side could possibly be the culprits!

By Dr. Anja Scholze, Stanford University

See the rest here:
Twin Genetics and Heredity - Understanding Genetics

Medical genetics is the branch of medicine that involves the diagnosis and management of hereditary disorders. Medical genetics differs from human genetics in that human genetics is a field of scientific research that may or may not apply to medicine, while medical genetics refers to the application of genetics to medical care. For example, research on the causes and inheritance of genetic disorders would be considered within both human genetics and medical genetics, while the diagnosis, management, and counselling people with genetic disorders would be considered part of medical genetics.

In contrast, the study of typically non-medical phenotypes such as the genetics of eye color would be considered part of human genetics, but not necessarily relevant to medical genetics (except in situations such as albinism). Genetic medicine is a newer term for medical genetics and incorporates areas such as gene therapy, personalized medicine, and the rapidly emerging new medical specialty, predictive medicine.

Medical genetics encompasses many different areas, including clinical practice of physicians, genetic counselors, and nutritionists, clinical diagnostic laboratory activities, and research into the causes and inheritance of genetic disorders. Examples of conditions that fall within the scope of medical genetics include birth defects and dysmorphology, mental retardation, autism, and mitochondrial disorders, skeletal dysplasia, connective tissue disorders, cancer genetics, teratogens, and prenatal diagnosis. Medical genetics is increasingly becoming relevant to many common diseases. Overlaps with other medical specialties are beginning to emerge, as recent advances in genetics are revealing etiologies for neurologic, endocrine, cardiovascular, pulmonary, ophthalmologic, renal, psychiatric, and dermatologic conditions.

In some ways, many of the individual fields within medical genetics are hybrids between clinical care and research. This is due in part to recent advances in science and technology (for example, see the Human genome project) that have enabled an unprecedented understanding of genetic disorders.

Clinical genetics is the practice of clinical medicine with particular attention to hereditary disorders. Referrals are made to genetics clinics for a variety of reasons, including birth defects, developmental delay, autism, epilepsy, short stature, and many others. Examples of genetic syndromes that are commonly seen in the genetics clinic include chromosomal rearrangements, Down syndrome, DiGeorge syndrome (22q11.2 Deletion Syndrome), Fragile X syndrome, Marfan syndrome, Neurofibromatosis, Turner syndrome, and Williams syndrome.

In the United States, physicians who practice clinical genetics are accredited by the American Board of Medical Genetics and Genomics (ABMGG).[1] In order to become a board-certified practitioner of Clinical Genetics, a physician must complete a minimum of 24 months of training in a program accredited by the ABMGG. Individuals seeking acceptance into clinical genetics training programs must hold an M.D. or D.O. degree (or their equivalent) and have completed a minimum of 24 months of training in an ACGME-accredited residency program in internal medicine, pediatrics, obstetrics and gynecology, or other medical specialty.[2]

Metabolic (or biochemical) genetics involves the diagnosis and management of inborn errors of metabolism in which patients have enzymatic deficiencies that perturb biochemical pathways involved in metabolism of carbohydrates, amino acids, and lipids. Examples of metabolic disorders include galactosemia, glycogen storage disease, lysosomal storage disorders, metabolic acidosis, peroxisomal disorders, phenylketonuria, and urea cycle disorders.

Cytogenetics is the study of chromosomes and chromosome abnormalities. While cytogenetics historically relied on microscopy to analyze chromosomes, new molecular technologies such as array comparative genomic hybridization are now becoming widely used. Examples of chromosome abnormalities include aneuploidy, chromosomal rearrangements, and genomic deletion/duplication disorders.

Molecular genetics involves the discovery of and laboratory testing for DNA mutations that underlie many single gene disorders. Examples of single gene disorders include achondroplasia, cystic fibrosis, Duchenne muscular dystrophy, hereditary breast cancer (BRCA1/2), Huntington disease, Marfan syndrome, Noonan syndrome, and Rett syndrome. Molecular tests are also used in the diagnosis of syndromes involving epigenetic abnormalities, such as Angelman syndrome, Beckwith-Wiedemann syndrome, Prader-willi syndrome, and uniparental disomy.

Mitochondrial genetics concerns the diagnosis and management of mitochondrial disorders, which have a molecular basis but often result in biochemical abnormalities due to deficient energy production.

There exists some overlap between medical genetic diagnostic laboratories and molecular pathology.

Genetic counseling is the process of providing information about genetic conditions, diagnostic testing, and risks in other family members, within the framework of nondirective counseling. Genetic counselors are non-physician members of the medical genetics team who specialize in family risk assessment and counseling of patients regarding genetic disorders. The precise role of the genetic counselor varies somewhat depending on the disorder.

Although genetics has its roots back in the 19th century with the work of the Bohemian monk Gregor Mendel and other pioneering scientists, human genetics emerged later. It started to develop, albeit slowly, during the first half of the 20th century. Mendelian (single-gene) inheritance was studied in a number of important disorders such as albinism, brachydactyly (short fingers and toes), and hemophilia. Mathematical approaches were also devised and applied to human genetics. Population genetics was created.

Medical genetics was a late developer, emerging largely after the close of World War II (1945) when the eugenics movement had fallen into disrepute. The Nazi misuse of eugenics sounded its death knell. Shorn of eugenics, a scientific approach could be used and was applied to human and medical genetics. Medical genetics saw an increasingly rapid rise in the second half of the 20th century and continues in the 21st century.

The clinical setting in which patients are evaluated determines the scope of practice, diagnostic, and therapeutic interventions. For the purposes of general discussion, the typical encounters between patients and genetic practitioners may involve:

Each patient will undergo a diagnostic evaluation tailored to their own particular presenting signs and symptoms. The geneticist will establish a differential diagnosis and recommend appropriate testing. Increasingly, clinicians use SimulConsult, paired with the National Library of Medicine Gene Review articles, to narrow the list of hypotheses (known as the differential diagnosis) and identify the tests that are relevant for a particular patient. These tests might evaluate for chromosomal disorders, inborn errors of metabolism, or single gene disorders.

Chromosome studies are used in the general genetics clinic to determine a cause for developmental delay/mental retardation, birth defects, dysmorphic features, and/or autism. Chromosome analysis is also performed in the prenatal setting to determine whether a fetus is affected with aneuploidy or other chromosome rearrangements. Finally, chromosome abnormalities are often detected in cancer samples. A large number of different methods have been developed for chromosome analysis:

Biochemical studies are performed to screen for imbalances of metabolites in the bodily fluid, usually the blood (plasma/serum) or urine, but also in cerebrospinal fluid (CSF). Specific tests of enzyme function (either in leukocytes, skin fibroblasts, liver, or muscle) are also employed under certain circumstances. In the US, the newborn screen incorporates biochemical tests to screen for treatable conditions such as galactosemia and phenylketonuria (PKU). Patients suspected to have a metabolic condition might undergo the following tests:

Each cell of the body contains the hereditary information (DNA) wrapped up in structures called chromosomes. Since genetic syndromes are typically the result of alterations of the chromosomes or genes, there is no treatment currently available that can correct the genetic alterations in every cell of the body. Therefore, there is currently no "cure" for genetic disorders. However, for many genetic syndromes there is treatment available to manage the symptoms. In some cases, particularly inborn errors of metabolism, the mechanism of disease is well understood and offers the potential for dietary and medical management to prevent or reduce the long-term complications. In other cases, infusion therapy is used to replace the missing enzyme. Current research is actively seeking to use gene therapy or other new medications to treat specific genetic disorders.

In general, metabolic disorders arise from enzyme deficiencies that disrupt normal metabolic pathways. For instance, in the hypothetical example:

Compound "A" is metabolized to "B" by enzyme "X", compound "B" is metabolized to "C" by enzyme "Y", and compound "C" is metabolized to "D" by enzyme "Z". If enzyme "Z" is missing, compound "D" will be missing, while compounds "A", "B", and "C" will build up. The pathogenesis of this particular condition could result from lack of compound "D", if it is critical for some cellular function, or from toxicity due to excess "A", "B", and/or "C". Treatment of the metabolic disorder could be achieved through dietary supplementation of compound "D" and dietary restriction of compounds "A", "B", and/or "C" or by treatment with a medication that promoted disposal of excess "A", "B", or "C". Another approach that can be taken is enzyme replacement therapy, in which a patient is given an infusion of the missing enzyme.

Dietary restriction and supplementation are key measures taken in several well-known metabolic disorders, including galactosemia, phenylketonuria (PKU), maple syrup urine disease, organic acidurias and urea cycle disorders. Such restrictive diets can be difficult for the patient and family to maintain, and require close consultation with a nutritionist who has special experience in metabolic disorders. The composition of the diet will change depending on the caloric needs of the growing child and special attention is needed during a pregnancy if a woman is affected with one of these disorders.

Medical approaches include enhancement of residual enzyme activity (in cases where the enzyme is made but is not functioning properly), inhibition of other enzymes in the biochemical pathway to prevent buildup of a toxic compound, or diversion of a toxic compound to another form that can be excreted. Examples include the use of high doses of pyridoxine (vitamin B6) in some patients with homocystinuria to boost the activity of the residual cystathione synthase enzyme, administration of biotin to restore activity of several enzymes affected by deficiency of biotinidase, treatment with NTBC in Tyrosinemia to inhibit the production of succinylacetone which causes liver toxicity, and the use of sodium benzoate to decrease ammonia build-up in urea cycle disorders.

Certain lysosomal storage diseases are treated with infusions of a recombinant enzyme (produced in a laboratory), which can reduce the accumulation of the compounds in various tissues. Examples include Gaucher disease, Fabry disease, Mucopolysaccharidoses and Glycogen storage disease type II. Such treatments are limited by the ability of the enzyme to reach the affected areas (the blood brain barrier prevents enzyme from reaching the brain, for example), and can sometimes be associated with allergic reactions. The long-term clinical effectiveness of enzyme replacement therapies vary widely among different disorders.

There are a variety of career paths within the field of medical genetics, and naturally the training required for each area differs considerably. It should be noted that the information included in this section applies to the typical pathways in the United States and there may be differences in other countries. US Practitioners in clinical, counseling, or diagnostic subspecialties generally obtain board certification through the American Board of Medical Genetics.

Genetic information provides a unique type of knowledge about an individual and his/her family, fundamentally different from a typically laboratory test that provides a "snapshot" of an individual's health status. The unique status of genetic information and inherited disease has a number of ramifications with regard to ethical, legal, and societal concerns.

On 19 March 2015, scientists urged a worldwide ban on clinical use of methods, particularly the use of CRISPR and zinc finger, to edit the human genome in a way that can be inherited.[3][4][5][6] In April 2015 and April 2016, Chinese researchers reported results of basic research to edit the DNA of non-viable human embryos using CRISPR.[7][8][9] In February 2016, British scientists were given permission by regulators to genetically modify human embryos by using CRISPR and related techniques on condition that the embryos were destroyed within seven days.[10] In June 2016 the Dutch government was reported to be planning to follow suit with similar regulations which would specify a 14-day limit.[11]

The more empirical approach to human and medical genetics was formalized by the founding in 1948 of the American Society of Human Genetics. The Society first began annual meetings that year (1948) and its international counterpart, the International Congress of Human Genetics, has met every 5 years since its inception in 1956. The Society publishes the American Journal of Human Genetics on a monthly basis.

Medical genetics is now recognized as a distinct medical specialty in the U.S. with its own approved board (the American Board of Medical Genetics) and clinical specialty college (the American College of Medical Genetics). The College holds an annual scientific meeting, publishes a monthly journal, Genetics in Medicine, and issues position papers and clinical practice guidelines on a variety of topics relevant to human genetics.

The broad range of research in medical genetics reflects the overall scope of this field, including basic research on genetic inheritance and the human genome, mechanisms of genetic and metabolic disorders, translational research on new treatment modalities, and the impact of genetic testing

Basic research geneticists usually undertake research in universities, biotechnology firms and research institutes.

Sometimes the link between a disease and an unusual gene variant is more subtle. The genetic architecture of common diseases is an important factor in determining the extent to which patterns of genetic variation influence group differences in health outcomes.[12][13][14] According to the common disease/common variant hypothesis, common variants present in the ancestral population before the dispersal of modern humans from Africa play an important role in human diseases.[15] Genetic variants associated with Alzheimer disease, deep venous thrombosis, Crohn disease, and type 2 diabetes appear to adhere to this model.[16] However, the generality of the model has not yet been established and, in some cases, is in doubt.[13][17][18] Some diseases, such as many common cancers, appear not to be well described by the common disease/common variant model.[19]

Another possibility is that common diseases arise in part through the action of combinations of variants that are individually rare.[20][21] Most of the disease-associated alleles discovered to date have been rare, and rare variants are more likely than common variants to be differentially distributed among groups distinguished by ancestry.[19][22] However, groups could harbor different, though perhaps overlapping, sets of rare variants, which would reduce contrasts between groups in the incidence of the disease.

The number of variants contributing to a disease and the interactions among those variants also could influence the distribution of diseases among groups. The difficulty that has been encountered in finding contributory alleles for complex diseases and in replicating positive associations suggests that many complex diseases involve numerous variants rather than a moderate number of alleles, and the influence of any given variant may depend in critical ways on the genetic and environmental background.[17][23][24][25] If many alleles are required to increase susceptibility to a disease, the odds are low that the necessary combination of alleles would become concentrated in a particular group purely through drift.[26]

One area in which population categories can be important considerations in genetics research is in controlling for confounding between population substructure, environmental exposures, and health outcomes. Association studies can produce spurious results if cases and controls have differing allele frequencies for genes that are not related to the disease being studied,[27] although the magnitude of this problem in genetic association studies is subject to debate.[28][29] Various methods have been developed to detect and account for population substructure,[30][31] but these methods can be difficult to apply in practice.[32]

Population substructure also can be used to advantage in genetic association studies. For example, populations that represent recent mixtures of geographically separated ancestral groups can exhibit longer-range linkage disequilibrium between susceptibility alleles and genetic markers than is the case for other populations.[33][34][35][36] Genetic studies can use this admixture linkage disequilibrium to search for disease alleles with fewer markers than would be needed otherwise. Association studies also can take advantage of the contrasting experiences of racial or ethnic groups, including migrant groups, to search for interactions between particular alleles and environmental factors that might influence health.[37][38]

Read more:
Medical genetics - Wikipedia

A mouse ovary with proteins specific to oocytes labelled in red and yellow. The study reports that culturing such ovaries in the presence of a drug that inhibits DNA damage checkpoint enzymes protects the oocytes from lethal levels of radiation that would normally kill the entire oocyte reserve (small oocytes in picture). Credit: Schimenti Lab, Cornell University

An existing drug may one day protect premenopausal women from life-altering infertility that commonly follows cancer treatments, according to a new study.

Women who are treated for cancer with radiation or certain chemotherapy drugs are commonly rendered sterile. According to a 2006 study from Weill Cornell Medicine, nearly 40 percent of all female breast cancer survivors experience premature ovarian failure, in which they lose normal function of their ovaries and often become infertile.

Women are born with a lifetime reserve of oocytes, or immature eggs, but those oocytes are among the most sensitive cells in the body and may be wiped out by such cancer treatments.

The current study, published in the journal Genetics, was led by John Schimenti, Cornell University professor in the Departments of Biomedical Sciences and Molecular Biology and Genetics. The study builds on his 2014 research that identified a so-called checkpoint protein (CHK2) that becomes activated when oocytes are damaged by radiation.

CHK2 functions in a pathway that eliminates oocytes with DNA damage, a natural function to protect against giving birth to offspring bearing new mutations. When the researchers irradiated mice lacking the CHK2 gene, the oocytes survived, eventually repaired the DNA damage, and the mice gave birth to healthy pups.

The new study explored whether the checkpoint 2 pathway could be chemically inhibited.

"It turns out there were pre-existing CHK2 inhibitor drugs that were developed, ironically enough, for cancer treatment, but they turned out not to be very useful for treating cancer," said Schimenti, the paper's senior author. Vera Rinaldi, a graduate student in Schimenti's lab, is the paper's first author. "By giving mice the inhibitor drug, a small molecule, it essentially mimicked the knockout of the checkpoint gene," Rinaldi said.

By inhibiting the checkpoint pathway, the oocytes were not killed by radiation and remained fertile, enabling birth of normal pups.

"The one major concern," Schimenti said, "is that even though these irradiated oocytes led to the birth of healthy mouse pups, it's conceivable that they harbor mutations that will become manifested in a generation or two, because we are circumventing an evolutionarily important mechanism of genetic quality control. This needs to be investigated by genome sequencing."

When doctors recognize the need for oocyte-damaging cancer treatments, women may have their oocytes or even ovarian tissue removed and frozen, but this practice delays treatment. Also, when women run out of oocytes, women's bodies naturally undergo menopause, as their hormonal systems shift.

"That is a serious dilemma and emotional issue," Schimenti said, "when you layer a cancer diagnosis on top of the prospect of having permanent life-altering effects as a result of chemotherapy, and must face the urgent decision of delaying treatment to freeze oocytes at the risk of one's own life."

The study sets a precedent for co-administering this or related drugs and starting cancer therapy simultaneously, though such interventions would first require lengthy human trials.

"While humans and mice have different physiologies, and there is much work to be done to determine safe and effective dosages for people, it is clear that we have the proof of principle for this approach," Schimenti said.

Explore further: Protein that culls damaged eggs identified, infertility reversed

Journal reference: Genetics

Provided by: Cornell University

Read more:
Drug may curb female infertility from cancer treatments - Medical Xpress

On Monday, the Memphis Zoo tweeted about their new baby flamingos the most recent in a long line of zoo babies we've met through the spring and summer.

Let's see ... there's been Winnie the hippo, two giraffes, a sloth, an orangutan, rare Louisiana pine snakes, a Yellow-backed Duiker, aFrancois langur, and a Spot-nosed Guenon named Grommet.

So what is going on? Has there been extra-sexy time at the zoo? Do we need to have a birds-and-the-bees talk with them? Is this all a PR stunt?

Matt Thompson, director of the zoo's Animal Programs, says that while springtime is a time for babies, reproduction at the zoo has been higher than average, and the push to get the public involved has also been higher than average.

The birth rate is all part of a bigger plan, bigger than the Memphis Zoo.

"Theres different programs for different species of animals Species Survival Plan (SSP)," Thompson explains. "For instance, there is a sloth SSP, and a hippo SSP and a giraffe SSP. What that is is a collection of zoo professionals, very smart people who analyze and look at the genetics of different lines of animals, so if the Memphis Zoo, for example, has a certain genetic line and a certain female that would really work well at the Indianapolis Zoo, they might put out a recommendation.They work their hardest to keep the gene pool healthy to prevent inbreeding and that kind of thing."

A prime example of the SSP at work is one little hippo named Winnie.

"Her mother and father both came to us from Disneys Animal Kingdom and they came as a result of an SSP recommendation. It was kind of win-win because Disney was getting a little full with hippos as you can imagine, hippos take up a lot of room," Thompson says. "We were building a new hippo exhibit and we needed a hippo or two, so we reached out to the SSP and they made recommendations based on genetics and thats how we wound up with these animals."

As for birth control, Thompson says it ranges from oral contraceptives to physically pulling the animals apart. And there are accidents. "Sure, just like with people, there are surprises. Not many, but every now and then," says Thompson.

Thompson says there are over 500 SSPs that cover all sorts of animals from pandas to lizards. The coordinator for the SSP for Louisiana Pine snakes, a rare species, is based at the Memphis Zoo.

Some of the toughest animals to breed are amphibians, and, yep, pandas.

"Its not for lack of trying," Thompson says. "Pandas are challenging because they ovulate about once a year and you have about a three-day window for them to get pregnant. Theyve got to tell you when they are ready [and] thats very challenging."

See the article here:
What's Up with All the Zoo Babies? - Memphis Flyer (blog)

Researchers recently determined that an existing drug may protect premenopausal women from infertility following cancer treatments.

A study funded by the National Institutes of Health with findings published in Genetics revealed the benefits of checkpoint protein (CHK2) in mice.

Officials said women treated for cancer with radiation or certain chemotherapy drugs are commonly rendered sterile adding women are born with a lifetime reserve of oocytes or immature eggs but those oocytes are among the most sensitive cells in the body and may be wiped out by cancer treatments.

Investigators said CHK2 functions in a pathway that eliminates oocytes with DNA damage, a natural function to protect against giving birth to offspring bearing new mutations. When they irradiated mice lacking the CHK2 gene, the oocytes survived and eventually repaired the DNA damage, with the mice birthing healthy pups.

It turns out there were pre-existing CHK2 inhibitor drugs that were developed, ironically enough, for cancer treatment, but they turned out not to be very useful for treating cancer, said John Schimenti, the papers senior author and Cornell University professor in the Departments of Biomedical Sciences and Molecular Biology and Genetics. The one major concern is that even though these irradiated oocytes led to the birth of healthy mouse pups, its conceivable that they harbor mutations that will become manifested in a generation or two because we are circumventing an evolutionarily important mechanism of genetic quality control. This needs to be investigated by genome sequencing.

See the original post here:
Drug may reduce female cancer patient infertility risk, according to study - Life Science Daily

For the new study, which was published in July in Carcinogenesis, researchers at Colorado State University, Memorial Sloan Kettering Cancer Center in New York City and the University of Michigan opted to focus on breast cancer. Epidemiological studies have shown that being physically fit is associated with lower risk for the disease, but not why.

Because they wanted to examine the role of innate fitness in the disease, the scientists turned to a famous strain of rats bred by Lauren Koch and Steven Britton at the University of Michigan. Over multiple generations, these rats were tested on treadmills. Those that ran the farthest before tiring were subsequently mated with one another, while those that pooped out early likewise were paired up, until, ultimately, the pups displayed a large difference in inborn fitness.

The researchers used female pups born to mothers with either notably high or low aerobic capacity. These young animals did not exercise, so their fitness depended almost exclusively on genetics.

Before the pups reached puberty, they were exposed to a chemical known to be a potent breast cancer trigger. The researchers then checked them frequently for palpable tumors throughout adulthood. They also looked, after the animals deaths, for signs of malignancies that had been too small to feel and microscopically examined breast cells for various markers of cell health.

The differences between the animals with high and low fitness turned out to be striking. The rats with low natural fitness were about four times as likely to develop breast cancer as the rats with high fitness were, and showed more tumors once the disease began. They also tended to contract the disease earlier and continue to develop tumors later in life compared with highly fit rats.

The contrasts between the two types of rats continued deep inside their cells. The researchers found almost inverted relationships in how certain aspects of the cells worked, and in particular, in the operation of what is known as the mTOR network. Shorthand for mammalian target of rapamycin, the mTOR network is a group of interlinked proteins within a cell that sense how much energy is available, depending on levels of oxygen and other factors, and let the cell know if there is enough energy around for it to divide and replicate.

In the rats with high fitness in this study, the mTOR networks typically produced biochemical signals that tell cells to avoid dividing much, while in the rats with low fitness, the mTOR networks pumped out messages that would generally promote cell division. Unchecked cell division is a hallmark of cancer.

Past studies have noted that women with breast cancer often show hyperactive mTOR networks.

Of course, this study involved rats, which are not people. But the findings have potential relevance for us, says Henry J. Thompson, the director of the Cancer Prevention Lab at Colorado State University and the studys lead author.

The study underscores the pervasive effects of fitness on bodily health, he says. Even without exercise, the pups born with high fitness were remarkably resistant to breast cancer in this study, he says, and showed fine-tuned cell function.

Most of us are likely to be able to raise our particular innate fitness capacity with exercise, he says.

In future studies, he and his colleagues hope to use the Michigan rats to learn more about the precise types and amounts of exercise that might best augment fitness, especially in those born with low capacity, and the subsequent effects on cell health and cancer risk.

See the original post:
Fitness May Lower Breast Cancer Risk - New York Times

Women were the adventurers of the early Bronze Age, moving around Europe and spreading culture as they went.

Thats the finding of a new study in the Proceedings of the National Academy of Sciences that used DNA to trace the origins of people who died in an area called the Lechtal, a valley in southern Germany and western Austria. Researchers analyzed the remains of 84 people buried there between 2500 and 1650 BCE, finding that most of the women had originally come from other places but migrated to the Lechtal as adults and were integrated into the society.

The scientists looked at both the womens genetics and the chemical makeup of their bones different geographical areas leave behind different signatures in their inhabitants.

With the genetic analysis, we see a great diversity of different female lineages, which would occur if over time many women relocated to the Lech Valley from somewhere else, researcher Alissa Mittnik said in a statement from the Max Planck Institute for the Science of Human History.

The isotope analysis, done on their molars, showed levels of the element strontium that also indicate the women were not from the area.

This woman was not born in the Lechtal but she was integrated into the society and buried there. Photo: Stadtarchologie Augsburg

Even though they were newcomers to the Lechtal, probably migrating from central Germany or from Bohemia, the western part of Czechia, the women were fully integrated, establishing families and later being buried in local cemeteries, which were linked to individual homes, in the same way the native people were. Over the generations, there could have been dozens of people buried in these cemeteries.

The men, on the other hand, usually stayed in the same area where they were born. This type of immigration pattern is known as patrilocal.

According to the researchers, the pattern of men staying put and women migrating into the Lechtal continued for hundreds of years in the villages along this fertile valley, as the Europeans were moving from the Stone Age to the Bronze Age.

The movement of the females may have played a significant role in the exchange of cultural objects and ideas, which increased considerably in the Bronze Age, in turn promoting the development of new technologies, the institute said. From an archaeological point of view, the new insights prove the importance of female mobility for cultural exchange in the Bronze Age.

The findings also tell scientists a little more about how humans moved around the continent during those prehistoric times.

Most of the women buried in prehistoric cemeteries in the Lechtal were foreigners to the community who were integrated into the society. Photo: Stadtarchologie Augsburg

Clues about those migrations are cropping up all the time, in more than just skeletons. Another study recently showed how people settled across Eurasia when they analyzed a wooden chest found in the Swiss Alps dating back to the early Bronze Age and found it contained the remnants of grains, including wheat. It helps to fill a gap in understanding about the beginning of agriculture and the diets of ancient people moving across the continents.

The genetic and isotope analysis performed on the bones of the women buried in the Lechtal are also helping to close a gap in information.

Individual mobility was a major feature characterizing the lives of people in Central Europe even in the third and early second millennium, lead researcher Philipp Stockhammer said in the statement. It appears that at least part of what was previously believed to be migration by groups is based on an institutionalized form of individual mobility.

Read the original:
Women Are Key To History Of Human Migration, Bones Show - International Business Times

An existing drug may one day protect pre-menopausal women from the infertility that commonly follows cancer treatments.

Women who are treated for cancer with radiation or certain chemotherapy drugs are often unable to have a baby later. A 2006 study showed that nearly 40 percent of all female breast cancer survivors experience premature ovarian failure, in which they lose normal function of their ovaries and often become infertile.

Women are born with a lifetime reserve of oocytes, or immature eggs, but those oocytes are among the most sensitive cells in the body and may be wiped out by cancer treatments.

The new study, published in Genetics, builds on earlier research that identified a so-called checkpoint protein (CHK2) that becomes activated when oocytes are damaged by radiation.

CHK2 functions in a pathway that eliminates oocytes with DNA damage, a natural function to protect against giving birth to offspring bearing new mutations. When the researchers irradiated mice lacking the CHK2 gene, the oocytes survived, eventually repaired the DNA damage, and the mice gave birth to healthy pups.

The new study explored whether the checkpoint 2 pathway could be chemically inhibited.

It turns out there were pre-existing CHK2 inhibitor drugs that were developed, ironically enough, for cancer treatment, but they turned out not to be very useful for treating cancer, says senior author John Schimenti, professor of biomedical sciences and molecular biology and genetics at Cornell University.

The one major concern is thatits conceivable that they harbor mutations that will become manifested in a generation or two

By giving mice the inhibitor drug, a small molecule, it essentially mimicked the knockout of the checkpoint gene, says graduate student Vera Rinaldi, the papers first author.

By inhibiting the checkpoint pathway, the oocytes were not killed by radiation and remained fertile, enabling birth of normal pups.

The one major concern, Schimenti says, is that even though these irradiated oocytes led to the birth of healthy mouse pups, its conceivable that they harbor mutations that will become manifested in a generation or two, because we are circumventing an evolutionarily important mechanism of genetic quality control. This needs to be investigated by genome sequencing.

When doctors recognize the need for oocyte-damaging cancer treatments, women may have their oocytes or even ovarian tissue removed and frozen, but this practice delays treatment. Also, when women run out of oocytes, their bodies naturally undergo menopause, as their hormonal systems shift.

That is a serious dilemma and emotional issue, Schimenti says, when you layer a cancer diagnosis on top of the prospect of having permanent life-altering effects as a result of chemotherapy, and must face the urgent decision of delaying treatment to freeze oocytes at the risk of ones own life.

The study sets a precedent for co-administering this or related drugs and starting cancer therapy simultaneously, though such interventions would first require lengthy human trials.

While humans and mice have different physiologies, and there is much work to be done to determine safe and effective dosages for people, it is clear that we have the proof of principle for this approach, Schimenti says.

The National Institutes of Health funded the work.

Source: Cornell University

Here is the original post:
Existing drugs may shield women from infertility after cancer - Futurity: Research News

Eddie Izzard will be running more marathons.The 55-year-old comedian and actor who ran 27 marathons in 27 days last year has revealed he will be donning his running shoes again in the future as he admitted the challenge he underwent in 2016 was very tough going.Speaking exclusively to BANG Showbiz at the UK premiere of Victoria and Abdul at the Odeon in Leicester Square, he said: Well I am doing more marathons but cannot say anything as of yet. There will be more marathons, there will be more languages, there will be more films I am going to make. It was very tough.The double marathon on the last day, 11 hours and 5 minutes running, that was not easy but I got the picture on my watch. I got about 6500 calories burned in that one day and ran at 7.6km an hour. It is a long way to run it. But I got it done. It is a salute to Nelson Mandela as well. The generosity of the UK public; in the end, we got about 2.6 million.Meanwhile, Eddie previously revealed he cant bear it when people refer to him as a transvestite a person who dresses in clothes appropriate to the opposite sex because he has female genetics.He explained: Im not a transvestite. I have some of the same genetics as women, so Im transgender. When I see a pair of nice heels, I think, Yeah that could work. That could be kind of fun, kind of sexy. Anyone can feel that. Were obsessed with the differences between someone with a penis and someone with a vagina. Everyone should calm down and take a chill pill.

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Eddie Izzard planning more marathons - Divine.ca

When it comes to female facial hair, there are awesome women like Harnaam Kaur who wear their hair with pride, and there are others want it removed ASAP.

Neither approach is wrong, but it's safe to say the latter is the more common.

But what actually causes female facial hair, and what are the best ways to safely remove it?

Getty

There are many different factors that can contribute to a woman experiencing some facial hair growth, and they range from hormonal imbalances (which can be quite severe) to genetics.

"It's actually very common, and most of the time people don't see it as a medical problem," Dr Adrian Lim, a spokesperson for the Australasian College of Dermatologists, told HuffPost Australia. "And the causes are simply racial and genetics.

"There are certain races which are more prone to facial hair, for example, Chinese and Japanese people might be more hairless and then you have southern Indians who might be more susceptible.

"But many social and cultural groups where is considered normal don't see it as problem at all."

Harnaam Kaur is a body confidence activist who wears her beard with pride.

"It is one of those things that does become more common around menopause, where sometimes a woman will develop coarse dark hairs on her top lip or chin or neck," CPCA spokesperson Dr Mary Dingley told HuffPost Australia.

"With younger people it's more of a genetic thing, and race can have an impact. Mediterraneans, so Greeks and Italians, and some Spanish people, and certainly Indian ladies tend to suffer from this a lot more than people from northern European climates."

Another contributing factor could be polycystic ovaries, which can result not only in facial hair but other problems such as acne.

This really depends on what sort of hair you have, how much there is and the reason as to why you have it.

"For someone with polycystic ovaries, there are other things to consider, such as trying to lose some weight if that's an issue," Dingley said. "You'd also look at the skin to see what was going on in terms of acne and oil control.

"For some people, even the contraceptive pill can be a useful thing, but that's something to be discussed with your doctor.

"For most people, they just have hair and that's their genetic make up or time of life."

Sebastien_B via Getty Images In some cases, the contraceptive pill can help.

The simplest methods, which are appropriate if you don't have much hair, can be DIY jobs you can do in the comfort and privacy of your own bathroom without too much worry.

"I mean obviously if it's just one hair or two, pluck them out," Dingley said. "Though this can be a bit difficult if your eyesight isn't so good.

"For ladies getting older this can be more difficult as time passes, though you can get good magnifying mirrors these days."

Other obvious options include bleaching and waxing, though those with sensitive skin may run into problems.

"For some people the bleaching and waxing irritates their skin too much, and threading can cause ingrown hairs, meaning you end up with this lumpy pustular thing as well as the hair," Dingley said."Then of course the hair is still coming through.

"While these methods are simple to perform, they still have possible side effects and they certainly don't offer long-term solutions. [The area of concern] will need constant maintenance."

Getty Images/iStockphoto Waxing is one short-term option, but it is painful and can cause irritation or ingrown hairs.

Still, for many people it's enough to get by. Where things become more complicated is if the above methods aren't working for some reason, or the hair growth is too much for an individual to handle.

"For some of the ladies who have almost a full on beard, it's not really something they can deal with themselves," Dingley said. "We also see transgender ladies who are looking to remove their facial hair permanently."

This is where something like a laser treatment steps in, but Dingley is keen to stress it's not for everybody.

"It needs to be done properly and well with the skin type and hair type in mind," she said. "Lasers work on the colour [of your skin] so darker skin types need to be careful.

"And the lighter and finer the hair, less likely it is for the treatment to be successful. For those who have light hair or colourless peachfuzz hair, it's not going to work.

Getty Images Spending time in the sun? Hold off on your laser treatment.

"The ideal person for laser treatment has paper white skin and coarse black hair. Which is actually pretty rare."

It's not a one-stop fix, either, with patients having to return for subsequent treatments, though Dingley says in most cases they should start seeing results after three to four sessions.

"We can target specific hairs or we can do the full on beard. Obviously it will be a bigger treatment if you have more hairs there, and obviously the times for each person vary," she said.

Dingley also cautions against side effects and says anyone with a suntan needs to hold off on their laser treatments for a couple of days until the tan "settles down".

"I think it's important to warn people there can be side effects and complications, the most common one being a burn," she said. "That's why we really try to encourage people to go to someone who knows what they are doing and who understands skin types and hair.

"Not some backyard operator flashing lightbeams around who doesn't understand the potential consequences.

"It's also important to keep the sun off the area, protect yourself from the sun, and don't go and get a treatment if you have a tan.

"It really is that important."

Read more:
Unwanted Facial Hair? Here's How To Get Rid Of It - Huffington Post Australia

By Giorgia GuglielmiAug. 31, 2017 , 2:13 PM

The saying you are what you eat is particularly true for female honey bees, which grow up to be either small, sterile workers or large, fertile queens depending on their diet. Previously, many researchers thought that something in the food fed to young queensa secretion called royal jellywas what made the difference. Now, a new study suggests its signaling molecules in the grub of young worker bees that keeps their sexual development in check. That diet, a mixture of pollen and honey called beebread, is shot through with a special kind of microRNA (miRNA), noncoding RNA molecules that help regulate gene expression. To find out whetherthese miRNAs were the culprit, scientists added them to the diet of larvae raised in the lab. These larvae developed more slowly, with smaller bodies and smaller ovaries than larvae fed food without the supplement, the team reports today in PLOS Genetics. The researchers also found that one common, plant-derived miRNA in beebread switches off a gene that helps larvae turn into queens. After being eaten with food, the miRNAs might enter the bees gut and spread throughout the rest of the body, where they could help regulate key genes, the scientists say. Although plant miRNAs alone arent likely to turn queens into workers, queens-to-be probably dont want to eat the commoners bread.

Read the rest here:
Why some baby bees are destined to become workersor queens - Science Magazine

Chandigarh: For the first time, dairy farmers will now have the option of sexed semen for desi cattle breeds like Sahiwal, Gir and Red Sindhi cows and Murrah buffaloes. Sexed genetics, which is used to produce offspring of a desired sex, was not available for these breeds till now. ABS India (ABS), a division of Genus Plc, on Thursday launched 'sexed dairy genetics' in Chandigarh. The technology is designed to deliver more high-value pregnancies to dairy herds countrywide. Priced differently for different genetics, ABS Sexcel will be available to the Indian dairy farmers at approximately 30-40% less than the import price of the sexed semen. At a press conference to announce the launch, British deputy high commissioner, Andrew Ayre said, "It is an important day for the UK and the Indian dairy industry to extend Sexcel benefits to Indian dairy farmers, helping them to double their income by 2022 as targeted by the government." Arvind Gautam, managing director, ABS India said it would give farmers a new option for achieving their desired genetic blueprint and would help them profit through genetic progress. "We have a unique product and trial results are very effective. For the first time, sexed semen of indigenous cattle breeds like Sahiwal, Red Sindhi and Gir cows and Murrah buffaloes is available in India." Rahul Gupta, head (production) of the company added, "Dairy farmers may now breed their cows with the sexed genetics specifically designed to produce more female cows using this new technology. The technology produces female sexed semen through a new, cutting edge, laser-kill technology."

See original here:
Dairy farmers can get sexed semen for native cattle breeds within India - Times of India