The airliner attacks on the World Trade Center (WTC) in New York City and on the Pentagon in Washington D.C. by al-Qaeda terrorists on Tuesday, September 11, 2001, finally and forever put the world on notice that life as we knew it had changed significantly. The aftermath of those attacks also spawned a new era of technology development in a quest to identify those who perished at the World Trade Center. Although DNA had played a significant role in the identification of victims of other mass fatality events, the WTC DNA identification effort created unprecedented emotional, technological, and organizational challenges. These challenges were met by public/private partnerships that enhanced and created new technology to meet the needs of this human tragedy.

On that beautiful, sunny day, one of us (RCS) was in a staff meeting when a criminalist (Ralph Ristenbatt III) in the laboratory asked permission to help set up a temporary morgue at the WTC where a small plane had allegedly and accidently smashed into one of the WTC towers. We soon learned that it was no accident, and it was no small plane. In fact two airplanes had smashed into the World Trade Center towers, first the North and then the South. America was under attack! After the twin towers fell, we realized that identifying the human remains would require nonexistent resources and that DNA could be the primary identification modality versus other common methods: fingerprints, dental, and X-Rays. As we near the ten-year anniversary of the WTC attacks, this report provides a retrospective of the DNA testing used in identifying the human remains recovered from the WTC site and how this tragic event pushed DNA bone extraction technology to new levels.

At the eye of the storm were the people at the New York Office of the Chief Medical Examiner (OCME). Although the OCME DNA laboratory was the largest forensic DNA laboratory in the United States, the initial estimates of the missing (20,000—the actual number turned out to be 2,952) meant that there would be a laboratory capacity issue. The OCME needed help! Some of the issues included: 1) No bar coding system, raising the issue of sample mix up. 2) Specialized software to compare DNA profiles and to make parentage-type identifications did not exist. 3) While we didn’t know it on that first day, the conditions at the WTC site promoted extensive human remains decomposition, which raised the possibility that STR testing might fail. The broader question then became important: what type of DNA testing should be employed for the long haul? 4) This would be a resource demanding project. 5) How should we collect ante-mortem DNA? 6) Where and how would we store the DNA data?

In addition to these issues, one that was to become the Achilles heel of the project concerned the analysis of bones. Bones coming into the laboratory were increasing rapidly, and because the heat and humidity at the WTC site accelerated the degradation of the DNA, the numbers and backlog were increasing exponentially. The issue was this: A robust, reliable, and rapid method for extracting DNA from bones did not exist. Over time and for reasons other than just numbers of samples, as the timeframe of the identification increased, bones would become the most reliable and eventually the only method for making identifications. The OCME did not have the capacity to analyze such a large number of bones in a reasonable timeframe.