Sex determination of human remains from peptides in tooth enamel

The assignment of biological sex to archaeological human skeletons is a fundamental requirement for the reconstruction of the human past. Determining the sex of human remains has implications ranging from the archaeological to legal contexts. DNA sequencing can be used for sex determination, but the approach is expensive, time-consuming, and depends on the quality of the DNA sample.

Dr Nicolas Stewart at the University of Brighton, together with colleagues at Durham University and the University of Sao Paulo, have developed a method for the sex determination of human remains using peptides from tooth enamel, the most durable human body tissue. To extract peptides from tooth enamel, the method uses a minimally destructive acid-etch procedure. Subsequently, sex chromosome-linked isoforms of amelogenin – an enamel-forming protein – are identified from the acid-etch sample using nano-liquid chromatography mass spectrometry. The researchers tested the method in studies on the remains of seven adult individuals from the late nineteenth century as well as male and female pairs from three archaeological sites ranging from 5700 years ago to the sixteenth century in the United Kingdom. In each context, the method successfully determined the sex of the individuals, as confirmed by comparison with coffin plates or standard osteological analyses.