WASHINGTON - Are they dead or alive?
The answer to that question about Saddam Hussein and his sons may hinge on analysis of DNA recovered from the latest coalition attempt to decapitate Iraqi leadership, military officials and civilian experts said yesterday.
A U.S. Air Force B-1B bomber Monday dropped four 2,000-pound bombs on the Baghdad restaurant where Saddam was believed to be meeting with his top aides.
The strike blasted a 60-foot-deep crater into the ground and turned at least three buildings into rubble.
U.S. Army Brig. Gen. Vincent Brooks said the explosions were so powerful that identification of human remains could be difficult.
“Like other places, it is possible that we may never be able to tell who was present without some detailed forensic work,” General Brooks said at a briefing from Central Command.
The site was still under Iraqi control, and General Brooks indicated that forensic teams had not been able to start their work. News accounts said Iraqi rescue workers had removed at least two bodies and were searching for at least a dozen more.
Bodies can be identified from facial features; physical clues, such as scars and old surgical procedures; clothing; jewelry, and other personal effects. The gold standards for positive identification, however, are fingerprints, dental records, and DNA - especially DNA when only fragments of human tissue remain.
Blast damage at the Baghdad site would not prevent DNA testing, according to an international expert.
“I believe it may be much easier than DNA identification at the World Trade Center,” Dr. Victor W. Weedn said. “It is likely that they will find relatively small fragments of tissue, rather than whole bodies, so DNA analysis may be very important.”
Dr. Weedn, who is with Carnegie Mellon University in Pittsburgh, pioneered standard DNA analysis methods used by crime laboratories worldwide. He envisioned, organized, and ran the U.S. Department of Defense DNA Registry, the military DNA identification program, while at the Armed Forces Institute of Pathology here. It maintains millions of DNA samples from all military service members.
A whole strand of DNA consists of 3.2 billion chemical “base pairs” and would stretch about five feet if uncoiled.
Forensic scientists work with small segments of the strand. They try to match the DNA sequence in a tissue fragment with DNA from victims.
The DNA may be “banked,” like the military DNA register, or left behind on combs, toothbrushes, and other items that victims used.
Heat from long-smoldering fires and water used to extinguish the blazes made identification efforts in New York more difficult because they broke the DNA into fragments that sometimes were too short to match.
Remains of 40 percent of the World Trade Center victims have not yet been identified, even with advanced DNA analysis techniques that can use fewer base pairs.
Fires did not appear to be blazing at the Baghdad site, and rescue workers were not pouring large amounts of water on it. As a result, DNA may be in better condition for analysis, Dr. Weedn said.
“That still leaves the problem of `reference' DNA,” Dr. Weedn added. “I believe there is a likelihood they will find some DNA. But what do they compare it to?”
By some accounts, the Central Intelligence Agency does have a sample of Saddam's DNA, extracted from a razor blade or tea cup that an estranged mistress supposedly purloined from a presidential palace.
“I wouldn't be too surprised if they don't have his DNA,” Dr. Weedn said, citing the difficulty in confirming that such an object really was used only by Saddam.
Other users could contaminate the object with their own DNA and make it useless for forensic testing.
In that case, DNA from Saddam's family members, including daughters Raghad and Rana, could help.
The CIA reportedly requested DNA samples from Osama bin Laden's family last year.
They were used to test against tissue fragments recovered from the site in Afghanistan where a Hellfire missile hit suspected al-Qaeda leaders.
“Let's assume they don't have his DNA,” Dr. Weedn continued. “But the analysis from the 14 or so bodies shows a father and two sons.” That, he said, could become good evidence that Saddam and his sons Qusay and Uday are dead.