WITH THE POSSIBILITY that Saddam Hussein was killed last week in the bombing near a Baghdad restaurant, there has been much speculation over whether allied authorities will be able to positively identify his remains. The blast was so intense (it left a 60 foot hole and shattered windows 300 yards away) that recovery of a body seems unlikely. But using the same technology used in both criminal investigations and the aftermath of the World Trade Center attacks, scientists can take minuscule bits of skin and tissue and analyze DNA. If two or more bodies have become intertwined, as they are sometimes in crashes and bombings, then scientists have to “worry about getting a clean profile,” says John Ryan, director of forensic programs at Myriad Genetics, the company that analyzed DNA samples from the World Trade Center. In that situation, scientists would look for the biggest pieces of human remains and cut into them to get a clean, untainted biological profile.
Once the forensic scientists have their samples, they search each one for 13 to 16 distinctive stretches of DNA called short tandem repeats (STRs). These markers are positioned along specific chromosomes and give a unique characteristic profile that can almost positively identify a person. The chances of duplicating each stretch is about 1 in 250 trillion. “The power of discrimination in this process is incredibly dramatic,” Ryan says.
