A male DNA sample taken from pants worn by Heather Barnett did not match that of defendant Danilo Restivo, Winchester Crown Court heard today.

Forensic scientist Carole Evans told the jury that she analysed three pieces of material from the pants, two bloodstained and the third unstained.

The two bloodstained pieces produced no results but the last section gave up a male DNA profile, but it was not from Restivo.

Restivo, 39, denies the murder of Heather Barnett at her flat in Capstone Road on November 12 2002.

Mrs Evans said the DNA profile matched that of Terry Marsh – Heather’s son or Terry’s father David.

But she said such a mixture of DNA would not be unusual in any household.

Mr Michael Bowes, QC, prosecuting asked her: “It would not be surprising, would it, if there was a perfectly innocent explanation for that? That is was the result of shared innocent household DNA crossover?”

Mrs Evans agreed that was perfectly possible.

She also said it was not possible to say what had given rise to the DNA sample. There was no evidence to establish whether the sample was blood or anything else.

Cross-examining, Mr David Jeremy QC, defending, asked Mrs Evans: “If you apply your statistics to an area of 20,000 males, we can expect to find fewer than 100 with a match. There will be a pool of people and the person whose DNA it is, will be drawn from that pool?”

That was correct said Mrs Evans.

Earlier Mrs Evans explained she had analysed three separate samples of hair – that found in Heathers’ right hand, under her left hand and some brown hair tied up with green cotton and found by police in a Tesco bag in Restivo’s bedroom in November 2006.

She compared the results with reference samples of DNA from Heather Barnett, Elisa Claps’ mother Filomena and brother Gildo, Restivo’s wife Fiamma Marsango and a number of other people.

The hair under Heather’s left hand was a match for her own, but none of the samples were a match for Elisa Claps, which would have been the same as her mother’s. The testing method was a specific process on maternal DNA.

The case continues.