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Victims' Families Turn to DNA Testing for Answers

For two weeks, Mohamed Derra remained hopeful that his 40-year-old brother, Traore Kareem, would be rescued from the huge pile of rubble that is all that is left of the World Trade Center. On Friday, he joined thousands of others who are now seeking the grim truth that is buried there.

"Somehow we need some kind of closure," says Derra.

Traore Kareem was a cook at the World Trade Center. Derra dropped off his brother's comb at a makeshift medical examiners office so scientists can obtain DNA information from it. Eventually, Derra hopes, the DNA might help them identify his brother’s remains.

"I would like to have some kind of DNA proof of that before I can say that's it," says Derra. "I can call back home and tell them that he is gone."

It's unlikely that Derra will be able to make that phone call soon. Nearly 6,000 people are believed to have been trapped when the twin towers collapsed. Only a few hundred bodies have been pulled from the rubble.

"The recovery effort will take many months and the identification of the remains will take twice that long," says Dr. Brian Ward. Ward is a scientist at Myriad Genetics lab in Salt Lake City, one of three labs in the nation that will use DNA matching techniques to identify the remains. He says identification of some victims may be virtually impossible.

"The technical challenges that we face is to extract DNA from the victims," says Ward. "As you know, the victims has been in a tragedy and there's lots of physical shearing and chemicals that victims will be exposed to."

Scientists in New York, Maryland and Utah are comparing DNA samples taken from the remains to DNA samples collected from the relatives. And so far no DNA matches have been made.

"There are over five to seven thousand people at the World Trade Center, and the challenges are going to be to find relatives to take samples from personal effects to make that match it's a complicated biological problem, as well as a identification problem," says Ward.

Only a few of the victims will be identified through traditional techniques of matching birthmarks or dental records. The majority will be identified through DNA samples. While thousands of tissue samples have already been recovered from the debris, the final number collected could top one million.

"This is largest effort of its kind in the world. It eclipses the last effort by about 20 times," says Ward.

The job is expected to take at least 2 years with a cost in the millions of dollars.
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