for National Geographic Today
The destruction of the World Trade Center has led to the largest and
most gruesome forensics project in history.
Rescue teams are working around the clock retrieving body parts from the rubble for DNA analysis. The combined impact of the plane crashes, fuel explosions, and collapse of the two towers burned and tore many bodies beyond recognition, so DNA analysis is the only way to identify the victims. No intact bodies have been found and there is little hope now that any exist.
As of two o'clock Wednesday afternoon, 109 people had been identified. But the number changes minute to minute, said Ellen Borakove, a spokeswoman for the New York City medical examiner's office.
The 109 identifications made so far were based on conventional methods such as fingerprints, unique scars, jewelry, and dental records.
As rescue workers discover human remains, all body parts are collected and sent to the medical examiners office, where each sample is logged.
Authorities in the office would not comment on how many samples have been received. Borakove did say, however, that Associated Press reports stating that "body parts are coming in 400 a day now, and the medical examiner's office is bracing for one million in all" are incorrect. Estimating the total number of body fragments likely to be recovered is impossible, she said, adding that "every sample will be tested."
Creating "Genetic Fingerprints"
Because the workers cannot determine whether various body parts are from the same victims, all the tissue found is being collected for testing.
It's also important to collect the samples so that once the victims have been identified, the remains can be returned to their families for last rites.
The New York City medical examiner's office has recruited two genetics companiesCelera Genomics of Rockville, Maryland, and Myriad Genetics of Salt Lake City, Utahto assist with DNA analysis.
Celera, known for its role in sequencing the human genome, and Myriad, which has played a major role in developing genetic tests to determine susceptibility to breast cancer, both have facilities for high-volume genetic testing.
Myriad Genetics will create a "genetic fingerprint" of each sample based on 13 regions, or loci, of the human genome that in combination present a unique profile.