hand, a forearm and a clavicle, and the DNA they carried, were all
investigators had to identify the remains of Timothy Stout, who
worked on the 103rd floor of the north tower of the World Trade
Two fingerprints and a dental pattern proved key to confirming
the death of David Suarez, who worked a few floors below.
A genetic analysis of a bone fragment determined the final fate
of John C. Hartz, who was on the phone with his wife describing the
horror of the first attack when the south tower, where he worked,
was struck by a second hijacked plane. "I have never been able to
understand why people have been so intent on recovering bodies,"
said Mr. Hartz's widow, Ellie. "Now I understand. It is a basic
human need. We are tactile."
These confirmations, achieved in the last month, are each
scientific miracles made possible by the largest forensic
investigation in United States history, one that is pressing the
limits of biomedical research even as it brings a painful mixture of
relief and fresh grieving to families. But these are just 3 out of
972 identifications that investigators have made as of Friday.
A third of the 2,824 victims of the World Trade Center attack
have now been identified, a number far beyond what many had thought
would be possible. The goal now, experts involved in the effort say,
is to use new scientific techniques to identify half or even
two-thirds of the victims, despite the miserably deteriorated state
of many of the remains being pulled from ground zero.
The endeavor spans the nation, from genetics laboratories in
Utah, Texas, Maryland and Virginia to law enforcement bureaus in
Washington and Albany; even a California forensic statistician is
helping. But the federally financed job, of course, is centered in
New York City, at the World Trade Center site, where remains have
been meticulously collected, and at the medical examiner's office,
at 520 First Avenue in Manhattan, where 18 refrigerated trailers
hold the evidence.
To date, 18,937 body parts have been recovered, along with 287
whole bodies. Most of the first successes in identifying victims
have come through traditional resources like fingerprints and dental
records, and those techniques are still yielding results. But
because of the extraordinary trauma involved in the towers'
collapse, DNA is often the only hope of matching remains to a name,
a family, a life story. In fact, through Friday, only 10 victims so
far have been identified solely by visual confirmation.
DNA, first used as a forensic tool in 1985, led to the
identification of all of the bodies in a Swissair plane crash in
1998 and an EgyptAir plane crash in 1999, two accidents in which
jets plunged into the Atlantic. In the days after the Sept. 11
attack, city officials announced that they felt compelled to test
each bit of human remains that could be found.
"This is an historic event of unprecedented magnitude, and the
question was if the scientific community could respond to that
need," said Mark D. Stolorow, executive director of Orchid Cellmark,
a genetics company. "The response has been surprisingly swift. We
are scientists, but we are also American scientists."
Progress has not come at an even pace. Only 2 of the 65 people
aboard United Airlines Flight 175, which struck the south tower,
have been identified, according to city records. By comparison, 182
of the 343 city firefighters, who wore protective gear, have been
Since the day of the attack, the identification effort has
proceeded simultaneously on multiple tracks. Dental records, details
on any tattoos, engraved rings or other unique items were collected
by the police, in the hope that traditional identification
approaches might be sufficient. But city investigators also started
immediately to assemble DNA from victims' families, who supplied
toothbrushes, razors, even lip balm used by a victim, which
presumably would contain his or her DNA. Cheek swabs from the
victims' relatives were also taken.
Each person's DNA, or genetic code, consists of a string of three
billion "base pairs," or large molecules, represented by the letters
"A," "G," "C," and "T." Sequences of those four molecules create the
code for all human characteristics, and variations in those
sequences make one person different from another. Those same
variations also allow DNA to be used like a fingerprint.
To start this effort, the city relied on a well-proven DNA
technique, called Short Tandem Repeat, in which the laboratories
looked for 13 different markers in each sample of human remains
collected from ground zero, measuring the size of each marker and
assigning the equivalent of a Social Security number to each
fragment of remains. An analysis would also be done on the 6,908
razor blades, combs, toothbrushes and other personal items, and the
6,889 cheek swabs from victims' relatives.
Myriad Genetics of Salt
Lake City and the Bode Technology Group of Springfield, Va., handled
most of this initial work. Bode alone has been sent 12,000 bone
samples, 5,500 soft tissue samples and 1,800 samples from family
members. The results are being sent back to the New York State
Police, and then the city medical examiner's office, where staff
members start on the difficult work of matching DNA profiles from
the remains with those from the family items and confirming the
accuracy of each step.
This effort gradually started to produce significant results: 57
DNA identifications in November, 69 in March and 92 in April, as of
Friday. But nothing is coming easily.
The fires that burned for weeks after the towers fell were so hot
that even when bones were recovered, they were often little more
than ash. The moisture at the site and bacteria caused further
degradation. The result is that nearly half of the first round of
samples tested at DNA labs have come back with incomplete profiles,
city officials said.
In as many as 700 cases, the medical examiner's office has been
unable to link a DNA profile that was isolated from a piece of
remains with any of the profiles established based on the items
supplied by the victim's families. Making the matches has become
almost an obsession for Dr. Robert Shaler, the director of forensic
biology with the city's medical examiner's office. He finds himself
at his office at 5 a.m., at his computer, again and again, trying to
make just one more match. He wonders as he arrives for work: "Can I
make matches? Can I make matches?"
Former Mayor Rudolph W. Giuliani said he already was amazed at
the success Dr. Shaler, and his boss, Dr. Charles S. Hirsch, the
city's chief medical examiner, have had. "I honestly think on the
evening of Sept. 11th, none of us who observed it, saw it, watched
it, were involved in it, ever thought you would have been able to
identify a third of the people," Mr. Giuliani said.
But Dr. Shaler and other city officials say they are far from
satisfied. They believe they have another eight months of work, as
they are just now pushing ahead again, in a second wave of
Celera Genomics, a Maryland
company best known for its work in sequencing the human genome in
recent years, is applying its fast DNA sequencing machines to the
World Trade Center identification effort. Celera's work, in
conjunction with its Applied Biosystems division, is focusing on
tiny rings of DNA in cell structures called mitochondria. These
maternally inherited rings are hardier than the long strands of DNA
used in the more traditional tests, and there are as many as 10,000
of them in each cell, giving investigators much more to work with.
This approach has been used before — including the 1994
identification of the remains of Czar Nicholas II of Russia — but
never before on such a large scale.
The city is also turning to techniques that have never been used
before in forensic investigations: single nucleotide polymorphisms,
known as snips, are telltale variations in single base pairs
scattered throughout the genome — an A instead of a T, say. The
snips can be found even when a victim's DNA has been broken into
fragments as short as 60 to 80 base pairs, much less than required
in the traditional tests, Mr. Stolorow of Orchid Cellmark said.
In preliminary attempts, the success rate for developing DNA
profiles of victims who could not be identified with the other
methods has been "encouragingly high," Mr. Stolorow said. The full
process of getting profiles, matching them with DNA from relatives
and other sources is expected to take two to three months, he
These incursions into uncharted scientific territory and even the
identifications that have come from traditional means have produced
a volatile amalgam of deep gratitude, a resurgence of September's
searing grief, the need to grapple with unfamiliar choices, and more
than a few surprises in the worlds of bereaved families.
One surprise lay hidden in the hopes of 12-year-old Brendan Regan
until the remains of his father, Robert Regan, a lieutenant in
Engine Company 205, Ladder Company 118 in Brooklyn Heights, were
found and identified on New Year's Day. The results came quickly,
based on dental records and a medal of St. Florian, patron saint of
firefighters, inscribed with his children's names.
"It turned out that up until that point, my son had held out an
unbelievable hope in his heart that he was still capable of having a
miracle occur," Lieutenant Regan's widow, Donna Regan, said. "He
felt my husband may have crawled to a safe spot" and somehow
survived, she said. Now, Mrs. Regan hopes, her son can begin the
long and difficult process of healing.
But the prospect that science could again and again identify more
of a victim's remains has put some families in a torturous limbo.
"We decided to hold off on the funeral," said Robert Alonso, whose
wife, Janet Alonso, worked for Marsh & McLennan on the 95th
floor of the north tower. Some of her remains were identified less
than two weeks ago.
"The last thing we needed was to have a service and then say,
`They've found more remains at ground zero,' " Mr. Alonso said.
The impact on families of techniques that can identify almost any
fragment of a loved one's remains is not always positive. "It's very
upsetting," one widow said of the news. "I almost threw up."
Given those emotions and the fact that dozens of distinct remains
are being found at times from a single victim, the medical
examiner's office is giving families the option of being notified
only once, when the first confirmation is made. They are also giving
families the alternative of leaving any identified remains at the
morgue until all testing is over, so that a single burial can take
Still, everyone expresses thanks for the monumental effort taking
place at ground zero and at labs across the country. The
identifications help families escape what Mrs. Regan calls the
"vanish factor": not having anything tangible on which to focus the
Mr. Alonso said thoughts of his children, ages 2 and 3, help him
cope with the upwelling of grief that the identification of his wife
has brought. "Questions will be coming as we get older: `Where's
Mommy? What happened to Mommy?' " Mr. Alonso said. A grave site, he
said, "brings me a place where when the kids get older and
understand, I can bring them and show them