Gina Gruenwald was a former Oklahoma State softball player with a bright future ahead of her when she was brutally stabbed to death in August 2004. Nearly seven years later, Billy Jene Wilson, a 42-year-old homeless man, has been arrested for her murder -- and all because he allegedly bit her wrist during the struggle to kill her.

According to the arrest affidavit, on view below, Gruenwald and some friends had hung out on the evening of August 20, 2004 at a bar called the Wave. She told them about a party in the vicinity of 13th Avenue and Humboldt Street and eventually dropped her off close by, even though they couldn't find where the bash was taking place.

The following morning, Denver Police recieved a call from a man who'd gone outside to grab the newspaper and spotted a body alongside his Lafayette Street house. The victim, later identified as Gruenwald, was lying on her back with blood under her head and a stained pocket knife on the ground nearby. Her pants were unbuckled, unzipped and slightly pulled down. Also found: a black duffle bag.

Surveillance video from a nearby Dollar Store was subsequently analyzed, and cops spotted a black male carrying a duffle bag like the one left near Gruenwald's body in footage from the evening before. But the key find was a bite mark on the victim's left wrist, which personnel from the crime lab swabbed in order to preserve any possible DNA evidence.

The DNA profile was later uploaded into CODIS, the Combined DNA Index System. And on April 11 of this year, Denver cops learned it scored a hit with Wilson, a transient who'd recently been arrested in San Francisco. Wilson had five arrests in Denver between 2004 and late spring 2005, for crimes such as possession of drug paraphernalia and panhandling -- the first on August 31, 2004 approximately ten blocks from where Gruenwald's body had been discovered.

The only problem, says Denver District Attorney's Office spokeswoman Lynn Kimbrough, is that Wilson had already been released; he was taken into custody on February 9, but let go on February 28. At that point, Kimbrough notes, "the officer asked, 'Can you go back and find him and take him into custody?' -- which they did.

"Without California taking DNA at the time of his arrest, he wouldn't have been identified," Kimbrough says, noting that Colorado has regularly acquired DNA samples of those arrested since last year.

Gruenwald's family is relieved that someone is finally being charged with Gina's slaying -- and all because of a single bite. "The DNA from our victim has been up there since 2004, just waiting for a match," Kimbrough points out. "And we finally got one."

Look below to see booking photo for Wilson, who'll seen be extradited to Colorado, as well as the aforementioned affidavit.

More from our Colorado Crimes archive: "Zachary Kocman, Joseph Murphy: Bias-motivated charges for yelling gay slur, assault."

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