"I would take them to the clean lab and at my work station I would open them up and then I would use a swab to swab around the inside of the pots that contained the samples to recover the DNA," he said.

"Once I'd done that, I'd have an extraction tube ready and you cut the tip off the swab and put it in the extraction tube for processing."

Mr Talbot said he would have carried out the process twice, keeping AJM40 and AJM42 separatefrom AJM46 and AJM48 to prevent contamination.

"The whole point of the clean lab is to prevent contaminating your sample with extraneous DNA," he said.

"There are safety cabinets for working in so the airflow is designed to prevent contamination and the labs themselves have a positiveair pressure."

Mr Talbot then added a chemical solution to the tubes with the swabs inside and they underwent a heating and spinning process for the DNA to be extracted.

He noted that the first time he tried to extract the DNA, it failed, as some of the chemical solution - the phenol - he had added to the tubes appeared frozen or crystallised.

He then added more phenol to the samples from a new bottle and repeated the process, which successfully separated the DNA.

A further several stages of the extraction were then carried out, with Mr Talbot estimating it would have taken a "few hours" to get to the final extract.

Witnesses were present for the key stages of the extraction process, to peer review Mr Talbot's workings.

The rest is here:
Claremont killer trial LIVE: Court sits into night for UK witnesses to give evidence on breakthrough DNA moment - WAtoday

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