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Archive for the ‘Female Genetics’ Category

The 50 Most Important Women in Science – Discover Magazine

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

Originally posted here:
The 50 Most Important Women in Science – Discover Magazine

12 Female Hormones Facts – Understanding your Hormones Today

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.

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12 Female Hormones Facts – Understanding your Hormones Today

Genetic Reasons: Female Hair Loss | Women’s ROGAINE

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.

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Genetic Reasons: Female Hair Loss | Women’s ROGAINE

Common ancestors of all humans (using genetics)

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)

The Genetics of Depression Are Different for Men and Women

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.

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The Genetics of Depression Are Different for Men and Women

Is Infertility Genetic? | Female Infertility Genetic …

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

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Is Infertility Genetic? | Female Infertility Genetic …

Twin Genetics and Heredity – Understanding Genetics

-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

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Twin Genetics and Heredity – Understanding Genetics

Medical genetics – Wikipedia

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]

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Medical genetics – Wikipedia

Drug may curb female infertility from cancer treatments – Medical Xpress

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

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Drug may curb female infertility from cancer treatments – Medical Xpress

What’s Up with All the Zoo Babies? – Memphis Flyer (blog)

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.”

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What’s Up with All the Zoo Babies? – Memphis Flyer (blog)

Drug may reduce female cancer patient infertility risk, according to study – Life Science Daily

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.

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Drug may reduce female cancer patient infertility risk, according to study – Life Science Daily

Fitness May Lower Breast Cancer Risk – New York Times

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.

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Fitness May Lower Breast Cancer Risk – New York Times

Women Are Key To History Of Human Migration, Bones Show – International Business 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.

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Women Are Key To History Of Human Migration, Bones Show – International Business Times

Existing drugs may shield women from infertility after cancer – Futurity: Research News

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

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Existing drugs may shield women from infertility after cancer – Futurity: Research News

Eddie Izzard planning more marathons – Divine.ca

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

Unwanted Facial Hair? Here’s How To Get Rid Of It – Huffington Post Australia

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.”

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Unwanted Facial Hair? Here’s How To Get Rid Of It – Huffington Post Australia

Dairy farmers can get sexed semen for native cattle breeds within India – Times of India

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.”

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Dairy farmers can get sexed semen for native cattle breeds within India – Times of India

Why some baby bees are destined to become workersor queens – Science Magazine

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.

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Why some baby bees are destined to become workersor queens – Science Magazine

Kansas researchers looking at new wheat varieties – San Francisco Chronicle

MANHATTAN, Kan. (AP) Research at the Kansas Wheat Innovation Center could revolutionize farming not just in Kansas but around the world.

Scientists there use advanced breeding techniques to isolate sought-after qualities. Different than genetic modification, breeding selects wheat varieties that need less water, can grow in extreme heat, or are durable against disease and pests in process that can take nearly a decade. Researchers at the Kansas Wheat Innovation Center hope to reduce that time so farmers can grow better wheat, faster, said Aaron Harries, vice president of research and operations.

This year, the wheat streak mosaic virus ravaged wheat crops in western Kansas. A tiny mite that remained active during an unusually warm winter spread the disease over a larger area than before. Within a few years, a variety of wheat resistant to the virus will be in the hands of farmers, Harries said.

But even as researchers develop tougher wheats, Mother Nature catches up. Disease evolves and climates change.

“We’re always striving to improve the yield,” he said.

This year, a consortium of international geneticists will likely finish sequencing wheat’s genome.

Similar to the Human Genome Project that mapped human genetics, the project, which began in part with the center’s research, will lay out the fundamentals of the wheat gene so scientists can more easily identify desirable traits.

It’s not just farmers that benefit from Kansas Wheat research. Varieties are being developed that are naturally sweeter, so bakers and food companies can use less sugar to sweeten doughs.

The Capital-Journal reports that researchers are also talking to the growing number of people who have celiac disease. Those with the condition are unable to digest gluten, a protein found in wheat, barley and rye. With clues unlocked in the wheat genome, the institute hopes to locate the specific portions of the protein that cause the reaction and breed it out or silence it, Harries said.

“That’s the protein that makes bread rise, so we’re not trying to make it ‘gluten free,'” he said. “We’re trying to make it ‘celiac safe.'”

To find the wheat qualities farmers and consumers want, researchers not only turn to wheat currently being grown, but they also have a store of ancient grains the wild grass varieties bred together to form modern wheat. Scientists collected the grains from places such as Syria, Iraq and Israel.

“We go treasure hunting for traits from those relatives and cross them into modern bread wheat,” Harries said.

With all these different types of wheat on the market, Harries said the Kansas Wheat Innovation Center sees a revolution coming in the way wheat is grown, sold and processed. Currently, farmers growing consumer grain sell it to the elevator at harvest, which turns it over to a company in the food industry.

In future, farmers may contract directly with a certain company to grow a specific type of wheat.

A farmer with 100 acres may grow 50 acres of consumer wheat, 25 acres of sweet wheat and 25 acres of celiac-safe wheat, Harries said.

“Ultimately that will change the way we grow wheat.” he said.

These advances in wheat are years away, but they begin in tiny pots in the institute’s more than 35,000-square-foot, $11 million facility. That’s where Heartland Plant Innovations research associate Tyler Suelter and a team breed new wheat varieties using a doubled haploid technique that can shave years off the breeding process.

Suelter said it sounds complex, but it’s really an acceleration of traditional breeding.

The process involves producing plants that have all the same genetics. When a variety is identified, scientists emasculate the plants, leaving only the female reproductive system.

Maize is used to pollinate the plant so an embryo is produced. Since the embryo wasn’t pollinated with wheat, it has half the number of chromosomes. Breeders will later double the count, so the plant has two copies of identical chromosomes a process that takes generations with typical breeding.

The research has produced nearly 100,000 doubled haploid variations and reduces the amount of time it takes to breed a new wheat variety.

“The time savings comes from how long it takes to grow the plants out. With (traditional breeding), you grow out several generations, and each takes six months,” Suelter said. “With doubled haploid, you basically fix those traits in a single generation.”

___

Information from: The Topeka (Kan.) Capital-Journal, http://www.cjonline.com

An AP Member Exchange shared by the Topeka Capital-Journal.

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Kansas researchers looking at new wheat varieties – San Francisco Chronicle

Women forces to be reckoned with in agriculture – Bizcommunity.com

Women have had to face many challenges within the workforce, particularly in the agriculture sector, which has traditionally been dominated by men. This changing, however, as more women are establishing themselves as forces to be reckoned with within the industry.

Although in different parts of the business, both women are focused on making the company and industry more sustainable. Nkala started her career at McCain South Africa through the company Graduate Trainee Program in 2004. Since then she has been promoted into different positions including being the first ever female production manager at the Springs plant, a position she holds today. Vorster followed her interest and passion for genetics and extension to McCain South Africa, where she is currently the only female Agronomist.

Both women have pioneered different techniques and implemented strategies to help McCain South Africa become more sustainable as a business.

Pumeza Nkala

Educating colleagues and employees on water became incredibly important. By making people aware of the drought and its effect, we were able to ensure that water usage was handled effectively and efficiently, explains Nkala. The water reduction strategy looked at technical elements like water cascading, process refinements and different process technologies. The result of this is that each of the plants now has a dedicated water usage team that reviews water usage results daily and proposes gap closing measures.

Since implementing this strategy there has been a 42% reduction in water wastage at the Springs plant and a 23% reduction at the Delmas facility over the past two years.

Ineke Vorster

As an agronomist, she plays an important role within the business. She looks at how varieties can help to optimise yields on the field and in the factory. This is made possible when crops are planted in the correct place and in the correct way. If the soil isnt perfect or the conditions are not favourable there could be a negative impact on the crops and this, in turn, will affect stock and what consumers will be able to buy. Not only could this affect the business and consumers, but the farmers as well.

Vorster goes above and beyond to ensure that the farms are sustainable and that the landscape can handle the planting in order to preserve and look after the growing crops and farms. I absolutely love everything about my job, the trial work is quite repetitive and you need to constantly look for answers and solutions. By actively being out there in the fields, you pick up on things that can sometimes be missed in theory, says Vorster. She says that it is the interaction with farmers, field officers and trying to find a solution to problems that they are facing that really gives her a thrill.

Both Nkala and Vorster want to encourage young women to follow their dreams and to not let anything stand in their way. We have all faced challenges in our lives but it is how you overcome them and rise above them that really matters. If you love what you do and are following your passion every day it really does make a difference, so dont settle for anything less than what you want, concluded Vorster.

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Women forces to be reckoned with in agriculture – Bizcommunity.com

Study: Drug may curb female infertility from cancer treatments – Cornell Chronicle

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.

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 Aug. 1 in the journal Genetics, was led by John Schimenti, Cornells James Law Professor of Genetics in the Departments of Biomedical Sciences and Molecular Biology and Genetics. It 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 papers senior author. Vera Rinaldi, a graduate student in Schimentis lab, is the papers first author. By giving mice the inhibitor drug, a small molecule, it essentially mimicked the knockout of the checkpoint gene.

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, 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, womens 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 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 said.

Ewelina Bolcun-Filas, a former postdoctoral associate in Schimentis lab and an assistant professor at The Jackson Laboratory in Bar Harbor, Maine, is the papers corresponding author.

The study was funded by the National Institutes of Health.

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Study: Drug may curb female infertility from cancer treatments – Cornell Chronicle

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The benefits of pregnancy diagnosis – Ohio’s Country Journal and Ohio Ag Net

We are entering an exciting time of the year for cow-calf producers. They have started or soon will be weaning their spring-born calves. Weaning is an excellent time to prepare the calf crop to become herd replacements or for future marketing opportunities by implementing health programs and transitioning to feed rations. It is also a great time to determine the pregnancy status of the breeding herd. Management practices for both these groups can go a long way to determine the ultimate profitability of herd.

The factor that should ultimately sort a female to the keep or cull pen is pregnancy status. The three primary methods used in pregnancy diagnosis are rectal palpation, ultrasound evaluation, or blood testing. Each these methods can effectively diagnose the females pregnancy status when properly implemented. Obviously the preferred result is for the female to be pregnant. Pregnancy diagnosis is relatively inexpensive, especially when you consider the potential savings of expenses it facilitates.

While variable costs such as feed have moderated somewhat lately, it is still fairly expensive to maintain a cow on an annual basis. Producers often fail to consider fixed costs such as machinery, buildings, management, and replacement animal expense. We do not have enough space in this article to debate a sample budget, but it is fair to say the annual carrying costs for a beef female can run from $700 to over $1,000 depending on the situation. An open female is not going to generate any income to help pay the bills.

Carrying an open female over to the next year or the next breeding season only compounds the accumulation of expenses.

In nearly every case, the producer would be better off selling the open female and replacing her with a bred female. This is particularly true of yearling females. If you cant get a properly developed, healthy yearling heifer bred in a 60- to 90-day breeding season, sell her as a heavy feeder calf or finish her out to harvest weight. If she is sub-fertile as a yearling, she will likely have fertility problems as a mature female.

At the risk of stating the obvious, the pregnant female is the foundation for any productive cow-calf operation. Hopefully the female will calve in a relatively short calving season that occurs during the months of the year that are best suited for your operation and time constraints. A pregnant female can also create some additional marketing opportunities for the producer.

Now is an excellent time to evaluate your herd and consider marketing decisions for the fall. Young, high quality cattle backed by solid genetics are in demand with potential buyers. Yearling heifers bred artificially to proven calving ease sires are very marketable. It is also a great time to evaluate the body condition of potential sale animals and make nutritional adjustments to the animals diet in anticipation of a sale date. It is my experience that while prospective buyers may complain about overly fat breeding cattle, they certainly resist purchasing breeding cattle that are in thin body condition.

One upcoming sale opportunity to consider is the 2017 Ohio Cattlemens Associations Replacement Female Sale on Nov. 24. Consignments for the sale are due to the Ohio Cattlemens Association by Oct. 2, 2017. Sale information can be obtained by contacting the Ohio Cattlemens Association at (614) 873-6736 or at their web site located at http://www.ohiocattle.org .

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The benefits of pregnancy diagnosis – Ohio’s Country Journal and Ohio Ag Net

7 Things Most Women Believe About Men And Sex (That Simply Aren’t True!) – FemaleFirst.co.uk

30 August 2017

By sex and relationship expert Tracey Cox

Tracey Cox

Men watch porn mostmen watch porn. But most men enjoy porn without binging on itandenjoy sex with their partners. Most dont replace one with the other.

Watching porn doesnt mean hes more likely to cheat either. In fact, if he has a higher sex drive than you and hes watching porn, chances are hes probably NOT cheating.

There are certain bits on human bodies that feel good sexually if theyre touched in the right way. Were hot-wired that way.

If you couldnt see and didnt know who was touching you, you could be turned on by anyone.

And I mean anyone.

While our brains most certainly contribute to what turns us on, theres a hell of a lot of anatomy at play also.

The term erogenous zone refers to places in our body that are packed with nerve endings so have heightened sensitivity.

The anus is one of them. Stimulate it effectively and he will feel pleasure – simple as that.

If he enjoys anal simulation, its because it feels good and hes comfortable enough in his sexuality NOT to be hung up on the this must mean Im gay myth.

Anal stimulation alone does not make him gay. Continually wanting to and having sex with other men is what makes him gay (or bi).

Some men do. Some women do as well. Some men also want to watch sport all the time. Some dont. Some men want to sleep all the time. Some dont. I think you get my drift.

There is continual and constant research on male versus female sex drives that turns up interesting and complex results. The implications are there are many factors at play, when predicting someones sex drive, not just gender.

The standard sex myth that says men want sex, women want love is pass and hopelessly out of date. In fact, research by online sex toy retailer Lovehoney found that sex with love was more important to men than women.

Plenty of things stop him getting hard too much alcohol, not feeling well, stress, performance anxiety, some medication, the need for more or different stimulation and the list goes on.

Contrary to popular belief, his penis isnt operated by a mechanical lever that moves to up whenever he sees a hot woman.

OK, well there might be something in that theory for the average 17-year-old but once grown-up life steps in, with all its pressures and stress, that soon disappears.

No doubt Donald Trump believes it but most (sane) men gave up on the Sorry I cheated honey but Im programmed to do it argument eons ago.

Women are still more socialized to restrict themselves to one partner but figures for the number of women having affairs continues to rise.

Were not animals we have brains and the ability to reason. Cheating is a choice not a biological need.

Psychologically, most men would probably prefer to have an erection during any sort of sexual activity even if penetrative sex isnt on the agenda.

Why? Because both sexes have been brainwashed to think desire equals a hard penis. It doesnt. (See above)

Arousal happens in the brain: he could be massively turned on giving you oral but still not be hard by time youve had an orgasm.

Turning you on is a huge erotic kick: your reaction is about to star in his next masturbatory session.

While there are a lot of things that can help me hold off orgasm and ejaculation, its also down to genetics. The size of his penis, how long his dad lasted (and his dad) all this is completely out of his control.

By all means try out all the tried-and-tested methods but after that, let it go and work around it if he doesnt last long.

Tracey has her own range of sex toys with Lovehoney, Britain’s biggest online sex toy retailer.

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7 Things Most Women Believe About Men And Sex (That Simply Aren’t True!) – FemaleFirst.co.uk

Kamagra gold 100mg review – Laughlin Entertainer

When an experiment turns into a tradition in Laughlin, it means there was a show worth taking a chance on at one timethen consistently that same show proved itself time after time to be one audiences didnt want to miss. The Memorial Day Comedy Festival at the Riverside Resort was that show. Experiencing comedy served up as a variety show with veteran comedian Gabe Lopez as the shows producer, performer and emcee was like discovering a hidden gem on the entertainment landscapemore along the lines of one of those underground clubs in Vegas, known only to a lucky few. But now the word is out and the Comedy Festival is coming back to the Riverside Resort over the Labor Day weekend this time.

If you are a local, or a regular visitor to Laughlinespecially if your visits are on holiday weekendsyou are aware that the Avi Resort & Casino doesnt simply wait for the Fourth of July to set off a major fireworks display. Nope. Beginning in 1996, and continuing every year since, they have been filling the skies above the Colorado River with the amped-up creations of Zambelli Internationale Fireworks on Memorial Day weekend, the Fourth of July and Labor Day weekend.

The Colorado Belle is home to a multitude of outdoor festivals that embrace particular themes and for the Labor Day Riverwalk Festival, its a celebration of the end of summer and the cooler temperatures just starting to take hold of the Colorado River regionthink of it as one big neighborhood block party.

Theres a lot to be said for being in the right place at the right time, but could Air Supplys long-time success be the result or a chance meeting or was the cosmos working overtime on a little something called destiny? Maybe, but one thing is for surenone of it would have been possible at all without their hard work and tenacity to make it happen.The two Russells, Graham Russell and Russell Hitchcock, happened to be cast in the same Sydney, Australian production of Jesus Christ Superstar in 1975, and everything changed after that.

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Kamagra gold 100mg review – Laughlin Entertainer

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