DNA Identification in Mass Fatality Incidents
Frederick Bieber
We knew immediately that hundreds of environmentally challenged samples would not yield full 13-locus STR profiles and would therefore require extra laboratory effort. So, early on, we explored alternate, novel technologies to help turn samples with only partial profiles into those that would allow solid victim identifications. In doing so, we carefully considered issues regarding genetic linkage of markers, and also agreed that only methods meeting NYS validation standards would be used.
Although all components of the DNA identification process are important, sample collection may be the most critical and frequently overlooked. In the urgency to identify the victims, there may be little attention paid to how the remains are collected. Planning can have a great impact on the quality and quantity of typable DNA. To standardize the collection materials—which, in turn, will simplify the extraction process—the laboratory manager should be involved in the sample collection process.
Protocols for chain-of-custody documentation in collecting evidence and handling samples must be a part of a laboratory’s mass fatality plan. This is important not only for scene reconstruction and quality control, but also for any subsequent legal proceedings. As in any situation with potential judicial implications, it is critically important to use the best forensic practices in collecting and preserving samples. Improper preservation methods can lead to the loss of typable DNA and the potential compromise of data that is necessary for a positive identification.
A mass fatality plan should provide for the collection of personal items from family members and others. After a mass fatality event, family members will be eager to provide samples to help identify a loved one. In a smaller incident, family reference samples may be easier to collect and analyze than a victim’s personal items. However, in a larger event, it may be more efficient to use personal items for identification, assuming sufficient quantities of DNA can be recovered from a personal effect and its sole use by the victim can be assured.
As noted in prior chapters of this report, cellular material can be derived from hair, stamps, envelopes, toothbrushes, razors, and unwashed clothing. If personal effects are used in a mass fatality identification effort, it is advisable to collect several samples, if possible, as some will be better suited for analysis than others. It can be challenging to develop instructions for submission of a victim’s personal items, including a way to ensure that only the victim used the item. Also, it is important to keep in mind that a family’s emotional attachment to a loved one’s personal item may be strong.
It also may be necessary to collect reference samples from around the world. In this case, it may be helpful to consult with professionals who work at paternity testing laboratories with remote sample collection experience.
Three sample forms that may provide general guidance are included with this report: Personal Items Submission Form (appendix B) , Family and/or Donor Reference Collection Form (appendix C), and the Family Tree Form (appendix D).
Needless to say, it should always be considered that a personal item may contain the DNA from someone other the victim/purported owner. That is why the Sample Personal Items Submission Form (appendix B) solicits detailed information regarding everyone who may have used the item. To prevent misidentification of remains due to the presence on the personal item of DNA from other contributors, the DNA profile recovered from the personal item should, if possible, be compared to the DNA profiles of family members to ensure that the proper biological relationship exists between the DNA on the personal item and the DNA from the family members.
