DNA Identification of September 11th Victims

The September 11, 2001 attack on the World Trade Center (WTC) in New York left thousands of people dead and a nation faced with the challenge of identifying the many people killed. Given the enormous number of victims, the state of their remains and the lengthy recovery by rescue workers, the effort was an intense one with a high level of pressure for forensic scientists in the United States.
Forensic scientists had the difficulty of identifying victims with samples that were degraded or damaged - requiring more advanced and sophisticated forms of DNA analysis to complete the task in a timely and accurate manner. Relatives and friends of those people in the WTC at the time of the attack had an exhausting and anxious wait. As such, providing information as quickly as possible was a key goal of the response to the attacks.
Value of Technology to Identify Victims
To identify the many victims, however, newer DNA analysis techniques used were extremely helpful to the recovery and identification effort. One technique involved a reduction in the size of a DNA fragment. Traditional DNA analysis methods have used techniques such as short tandem repeat (STR) analysis to analyse fragments of DNA from thirteen locations in DNA that differ among humans. In a fragment, there are base pairs of roughly two hundred to four hundred pairs that constitute a person's genetic fingerprint.In this relatively newer approach, the concept is somewhat of a modified version of STR analysis that involves smaller STR assays. The DNA fragments are still from those same thirteen areas but they are much smaller and have approximately twenty-five to one hundred and ninety base pairs, although this varies by the location itself. The benefit of the smaller size is that a DNA sample that has suffered from damage or degradation will still have pieces in the thirteen locations that are usable and can be analysed.