Claremont killer trial LIVE: Prosecutors nearing the end of Pathwest witness list

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Claremont killer trial LIVE: Prosecutors nearing the end of Pathwest witness list

Forensic scientist detailing DNA extraction of AJM41 and AJM46 fingernail samples

The next witness called is Pathwest forensic scientist Denise Downe, formerly known as Denise Galvin in 2003.

Prosecutor Carmel Barbagallo is asking Ms Downe about her involvement in the DNA extraction of Ciara's fingernail samples AJM41 and AJM46, in August 2003. 

It was requested a female staff member carry out the test, to reduce the risk of male DNA contamination. 

The results of the testing were detailed by forensic scientist, Aleksander Bagdonavicius, during his evidence yesterday

Earlier evidence from NZ forensic scientist SallyAnn Harbison revealed the control sample, or blank, on one of the extraction runs involving the testing of these two samples, at some stage became contaminated with a female's DNA that wasn't Ciara's. 

In preparation for the testing on August 22, Ms Downe took the fingernails out of their yellow top containers and took photographs of them, one at a time. 

She then undertook a process known as 'wet dry swabbing' where the nails were rubbed with a moistened cotton bud to recover any cellular material and then swabbed again with a dry cotton bud to collect any left over material. 

The two swabs were then placed into a tube and zip-locked in preparation for DNA testing in another section of the Pathwest lab. 

This process was repeated for each portion of nail (four pieces for AJM41 and two pieces for AJM46).

Of lab processes at the time, she has said:

"To try to prevent as far as possible, contamination ... we would wear personal protective equipment which consisted of the gown, face mask and gloves, and also benches we conducted the examination on would be cleaned prior to an examination and in between examinations."

She said the examination of the fingernails would have been done on a piece of clean blotting paper in the examination area of the lab. 

"[AJM41 and AJM46] would be treated as two separate item examinations, so ... I would have decontaminated that area, or cleaned the area ... so that consisted of discarding the paper into the bin, wiping the bench down ... retrieving separate instruments for the next examination," she said. 

Ms Downe said she would have used surgical steel forceps to collect the nail clippings out of their yellow top containers. 

Ms Downe said she also would have changed gloves and her face mask in between testing the two exhibits.

Day 45 of the trial to start at 10am

Welcome to WAtoday's live coverage of day 45 of the Claremont serial killer trial in the Supreme Court of Western Australia. 

Today, the state will likely call a new witness or read-in some statements of people unable to give evidence. 

The last-minute discovery of around 400-pages of Pathwest lab documents on Saturday led to the prosecution seeking a mid-week, three-day adjournment to alter the statements of the remaining Pathwest witnesses. 

The witnesses are Denise Galvin, Gavin Turbett and Scott Egan. 

It is not yet clear if any of these witnesses will be ready to give evidence this morning. 

In the coming days, the state also intends to call the Macro Taskforce detective who accompanied forensic scientist Laurie Webb to the UK with some of Ciara's fingernail samples in 2008.

It will then likely move onto its UK-based witnesses involved in the 2008 DNA testing, with late court sitting days flagged for Tuesday and Wednesday to allow for the time difference. 

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