The tests showed genetic material from a "single male source" was found on a vaginal swab taken from the accuser, but that material did not match any of the players, said attorney Joseph Chesire, who represents a player who has not been charged.
"In other words, it appears this woman had sex with a male," Cheshire said Friday night at a news conference with other defense attorneys. "It also appears with certainty it wasn't a Duke lacrosse player."
Two members of the team have been charged with raping a stripper hired to perform at the March 13 house party.
The dancer, a 27-year-old black student at nearby North Carolina Central University, told police she was raped and beaten for a half-hour by three white men. A grand jury has charged sophomores Reade Seligmann, of Essex Fells, N.J., and Collin Finnerty, of Garden City, N.Y., with rape, kidnapping and sexual assault.
Defense attorneys have insisted all the players are innocent, consistently pointing to an initial round of DNA tests they said found no match between the 46 players tested and the accuser.
"The first DNA report that came back indicated not a smattering, not a spider web of indication that there was any DNA from those boys anywhere around this woman. Now this is the second time that has happened," said attorney Wade Smith, who represents Finnerty.
Cheshire acknowledged that the second testing found some genetic material from several people on a plastic fingernail found in a bathroom trash can at the house. He said some of that material had the "same characteristics" — a link short of a conclusive match — to some of the players, but not the two who have been charged.
Along with the fingernail, the trash can contained cotton swabs, tissue, toilet paper and other items that would carry the DNA of people who used the bathroom, Cheshire said.
District Attorney Mike Nifong did not return a call to his home seeking comment Friday night.
After the first round of tests came back from a state crime lab without a match, Nifong said that in 75 to 80 percent of all sexual assault cases, there is no DNA evidence. In those cases, prosecutors had to proceed "the good old-fashioned way. Witnesses got on the stand and told what happened to them," he said last month.
But Stan Goldman, a Loyola Law School professor and former Los Angeles County public defender, said he would be surprised if Nifong went ahead with the case unless "they really have something significant that they are not revealing to us" — such as a lacrosse player willing to testify he saw a rape.
"There has got to be some really good prosecution explanation as to why the DNA evidence does not exist and why someone else's would be there," Goldman said.
That the players turned over the fingernail shows they had nothing to hide, Cheshire said.
"Is that consistent with someone that knowledgeably and knowingly committed a rape?" he said. "That they would leave fingernails that were ripped off a person in a violent struggle in their trash can after they're told there's an investigation and that police were going to come to their house, and when the police do, they give them the fingernails?"
According to a search warrant executed March 16, police recovered five fingernails from the house. It was unclear where those fingernails were found or whether they included the one containing DNA.
Nifong has said he hoped to charge a third person. He could do so as early as Monday at the next meeting of the Durham County grand jury.
Cheshire refused to say whether he thought his client would be charged.
"I hope it is none" of the players, he said. "It'll simply be accusing another innocent person."
The "single male source" who matched the genetic material found on the vaginal swab take from the victim is named in a report on the second round of DNA tests, which were done at a private lab. Cheshire said the man "is known to the Durham police department" but declined to give his name or the nature of his relationship with the accuser.
"There is no indication that this man should have his name dragged through the mud," he said.