One hair yields DNA profile

By Eugene Bingham and Alison Horwood

WELLINGTON - Only two of 400 hairs found on Scott Watson's bedding matched Olivia Hope's unusual reddish-gold hair type, a scientist said yesterday.

And of those two hairs, only one yielded the DNA clues necessary to indicate whether it belonged to Olivia.

Forensic specialists gave evidence at the Watson double murder trial yesterday about how they sifted through the hairs and other fragments found on a tigerskin-patterned blanket in the main sleeping cabin of his boat.

The 28-year-old Picton man denies murdering Olivia and Ben Smart after allegedly luring them on board his yacht in the Marlborough Sounds early on New Year's Day, 1998.

His trial in the High Court at Wellington has been going for nine weeks.

Susan Kathleen Vintiner, a forensic biologist with the Institute of Environmental Science and Research, said she examined two bags of hairs from the blanket at her laboratory in Mt Albert, Auckland, in March last year.

She was looking through the 400 hairs for blond strands to compare with a sample taken from Olivia's bedroom.

"I had to do the search twice because I was not satisfied that I would not miss something of interest."

On the second sift, she found two blond hairs, which she removed and put in individual bags.

"The hue was a gold-reddish colour which, in my experience as a hair examiner, is quite an unusual shade and colour."

Susan Vintiner said DNA for the testing she performed could be extracted only from the hair root or from the cellular material attached to it.

The roots of the two hairs were cut off, rinsed in sterile water to remove any trace material, and placed in plastic tubes for testing.

Only one produced a DNA profile, which Susan Vintiner said could then be compared with a sample of Olivia's genetic makeup obtained from a blood sample taken at birth.

The Crown has told the jury that DNA testing would show that the hairs matched Olivia's.

Evidence about this is expected to be called on Monday.

Susan Vintiner said she gave up looking for hairs belonging to Ben Smart after a preliminary examination of the material recovered from the blanket.

His hair characteristics, particularly the colour, "was going to make the task of finding any hairs that I could possibly attribute to him very difficult."

Questioned by crown prosecutor Kieran Raftery, she said most of the hairs taken from the blanket were brown or dark brown, similar to those of both Ben Smart and Watson.

"I decided I would not be able to identify hair microscopically that was more likely to come from Mr Smart than Mr Watson," said Susan Vintiner.

It would have taken several months of solid work to extract a profile from every hair on the blanket.

Mr Raftery: So the results you are giving us say nothing one way or another whether Ben's hairs were on that boat?

Susan Vintiner: No, I'm not able to comment on whether that is possible or not.

She also told the trial about the efforts she made to avoid contaminating the evidence, and to ensure that samples taken from Olivia's bedroom belonged to her.

She asked police to obtain more hairs from Olivia's home, as well as samples from her family and friends.

The hairs were all examined under a microscope to ensure that blond hairs belonging to people who associated with Olivia had not been confused with hairs belonging to the missing teenager.

Asked by Mr Raftery whether she had taken steps to keep Olivia's reference hairs separate from the hairs found on the blanket, she said: "It's very important to be very conscious of the possibility of contamination between reference samples and recovered samples.

"You are aware that might occur if utmost care is not taken during the procedure."