DNA inheritance

Using DNA to catch criminals has become common, but police in Denver, Colorado, this year demonstrated how the practice can be taken to a new level: They tracked down a suspect not through his DNA, but through that of his brother.

Here's how it happened, the Denver district attorney's office said:

In February 2008, two cars were broken into. Police found blood at both scenes and ran the samples through DNA databases but couldn't find a match. Then, as part of a study being conducted by the district attorney's office, investigators used new software to see whether the DNA in the blood was close enough to potentially be from a family member of someone in the criminal DNA database.
The software came up with six potential matches. Five didn't pan out, but one led police to a convicted car thief and, ultimately, that man's brother, Luis Jaimes-Tinajero.

Jaimes-Tinajero pleaded guilty in September to one count of criminal trespass and received a sentence of two years' probation.

Attempts to contact Jaimes-Tinajero for this report were unsuccessful.

District Attorney Mitch Morrissey called it one of the first cases in the country to use software to find familial DNA matches.

"Our hope here is to show that it works, which we have done," he said. "I think it's a valuable way to generate leads."

Morrissey's office developed the software tool with the Denver police, he said. He hopes to use it to solve murders, rapes and cold cases.

The matches to family members won't be used as evidence itself, he said, but rather as a way to generate leads for investigators to explore, similar to the way police may use a witness report of a partial license plate.

Would a man have DNA that matched his maternal grandfather? This is for a crime story, help, please!