THE remains of as many as 1,000 people lost in the World Trade Centre
attack might never be identified, according to the forensic biologist
leading the monumental DNA identification project.
The city medical examiner's office has identified slightly
more than half of the 2,792 people killed in the attack - only about
100 of those in the last year - as technicians struggled with DNA
degraded and damaged by fire and the elements.
Robert Shaler, chief of forensic biology, had once hoped to make 2,000
identifications, but he said he no longer considers that a realistic
Now, Shaler said he hopes for about 1,700 identifications - 1,800 at
the outside - by the time the office exhausts available DNA matching
methods within a year. City officials recently notified victims'
families of the outlook.
"I think once we've done all of the testing on all of the remains using
the technology we have, I think we're finished," Shaler said.
He cautioned that he does not mean the trade centre DNA effort would be
closed forever, but said it could not continue until new DNA processes
"If three years from now somebody comes up with something ... that
really looks like it's going to work, then we're going to be poised to
go after it," he said.
Identifications were made quickly in the weeks after the September 11,
2001, attack, many based on bodies recovered mostly intact. For smaller
parts, the medical examiner has had to rely on DNA matching, drawing
results from shreds of bone and tissue.
The medical examiner's office has been aggressive in finding new
avenues for DNA identifications, hiring companies to write software for
each technique they try. Right now, Shaler is hoping an adapted version
of a DNA process normally used for disease research will soon yield new
It lets technicians examine unusually short pieces of DNA, which
shrinks as it degrades. The DNA in about 61 per cent of the remains
recovered at the trade centre did not yield workable pieces in initial
tests because it was broken down by heat, humidity and time.
Shaler said the work in the next year would involve a tedious scrutiny
of the badly damaged DNA. The samples would undergo every available
process, each of which yield only partial results. Those test results
are then compared; for a successful match, the idea is that each test
fills in some of the gaps, like puzzle pieces fitting together.
"We're marrying different pieces of information together," Shaler said. "It's just this slow trickle."
Many of the new DNA matches made this year have yielded additional
remains for people already identified. The highest number of body parts
matched to one person is more than 200.
In most cases, victims whose remains have not been identified have been
legally declared dead by the court and their families issued death
certificates based on documents and other proof they were at the trade
centre or on the hijacked airplanes.
Shaler has begun looking beyond the lab to information about where
people worked in the towers, where and when their co-workers' remains
were found, and who in those groups have been identified. With that
data, the medical examiner's office can cross-reference identified
people with unidentified samples, narrowing the search to scrutinise a
few DNA profiles instead of hundreds.
Shaler came up with one potential match when he was experimenting
whether this technique was feasible. He then ordered software to be
created that would do it for him.
"I'm still driven by the families," he said.
"When I see these people, they look at me with eyes that say, 'Did you
find her yet?' But when you're only turning out a couple a week or
four, five a month, it's hard."
The Associated Press