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TITLE

Recovering Human Mitogenome Profiles from Chemically Treated U.S. Military Unknowns: The Intersection of Forensic and Ancient DNA

SPEAKER

Ms. Jacqueline Tyler Thomas

INSTITUTE

Armed Forces Medical Examiner System’s Armed Forces DNA Identification Laboratory (AFMES-AFDIL)

SUMMARY

At the Armed Forces Medical Examiner System’s Armed Forces DNA Identification Lab, our primary mission is to aid in the identification of fallen soldiers using DNA, and the vast majority of this work is focused on unknowns from past conflicts. While case samples range widely in quality, a subset of bone samples from the Korean War were chemically treated for preservation, including soaking in vats of formaldehyde and application of a powdered hardening compound. Due to degraded and cross-linked DNA, these samples fail using more traditional forensic methods, but related fields, such as ancient DNA, offer extraction and library preparation methods that prioritize short fragment retention. This presentation discusses the validation of MPS methods in a forensic lab and then focuses on the continuing work to improve success rates of our most challenging samples. In collaboration with the Max Planck Institute for Evolutionary Anthropology’s Department of Evolutionary Genetics, we compared forensic and ancient DNA extraction protocols, as well as one dsDNA and two ssDNA library prep methods. After hybridization capture enrichment and MPS, sample success was gauged in terms of recovery of the human mitogenome to validated forensic standards.