Forensic DNA Typing From Femurs and Bones of the Foot: A Study of 3 Cases

Evidence has been accumulating in the sense that femur may not always be the best option for DNA typing of skeletal remains. Recent studies have shown that bones of the hands and feet appear to be a superior source of preserved DNA. The current study reanalyzed DNA quantitation, degradation, and short tandem repeat typing in femurs, lateral cuneiforms, and distal foot phalanges. Data from 3 human identification cases involving corpses in an advanced decomposition state were collected. We found that in the studied cases, the femur provided equal or inferior results, recovering 84.9% of true alleles. Lateral cuneiforms (99.2%) and distal foot phalanges (96.8%) yielded higher percentages. In addition, more drop-ins and drop-outs were detected in femurs than cuneiforms and phalanges. This study adds to current findings that advocate for further investigation into bone selection for use in forensic practice. The impacts of our findings are limited by the small number of individuals studied and may not apply to old and degraded bones.