A man accused of killing five women around Ipswich had "prolonged physical contact" with three of them, a forensic scientist has told jurors.
The court heard Steve Wright's DNA was found on three of the women
Dr Peter Hau said there were extensive samples of DNA belonging to Steve Wright on Paula Clennell, Anneli Alderton and Annette Nicholls' bodies.
The three women and two others, Gemma Adams and Tania Nicol, were working as prostitutes when they disappeared.
Mr Wright, 49, on trial at Ipswich Crown Court, denies their murders.
Dr Hau told the court that in the cases of Miss Clennell, 24, Miss Alderton, 24, and Miss Nicholls, 29, the DNA was not likely to have come from "casual contact".
'One in a billion'
"I would say it would be more likely to be a prolonged physical contact," he said.
"Low-level" DNA had also been found on the three women but Mr Wright's DNA was the only common denominator found on each of them and it was virtually beyond doubt that it was Mr Wright's, the forensic scientist said.
"It is estimated the chances of matching a profile by chance is in the order of one in a billion," he said.
Dr Hau said there was no DNA link between the victims and Tom Stephens, a man whom jurors had been told knew all the women.
The bodies of Miss Clennell, Miss Alderton, Miss Nicholls, Miss Adams 25, and Miss Nicol, 19, were all found over a 10-day period in December 2006.
Semen-stained gloves were found in Steve Wright's car, Dr Hau said
Only remnants of DNA were found on the bodies of Miss Clennell, Miss Alderton and Miss Nicholls, who had been discovered in woodland, the court heard.
Dr Hau said: "A lot more DNA would have been lost when the bodies were exposed to the wind and rain.
"Therefore, the DNA must have come from a body fluid that is DNA-rich and which was deposited when wet."
On examining Mr Wright's Ford Mondeo car, seven "tiny flecks" of blood were found on the back seat and Dr Hau said the chance that it had not come from Miss Clennell was "one in 56,000".
Also in the car were gloves, stained with semen, which carried further DNA evidence.
"In my opinion, the findings provide very strong support for the view that Steve Wright was wearing the semen-stained gloves when he was in contact with Anneli Alderton and Annette Nicholls," Dr Hau added.
The court earlier heard the second day of evidence from pathologist Dr Nathaniel Cary, who had carried out post-mortem examinations on the bodies of all the women.
He told the court Miss Clennell, the last of the five women to be found dead, had been under the influence of heroin and cocaine at the time she died.
Examinations had revealed her neck had been "compressed", not long before her death, Dr Cary said.
The trial was adjourned until Friday.