Application of natural sciences methodology in archaeological study of Iron Age burials in Latvia: pilot study.

Natural sciences provide several modern methodologies that could be successfully applied in archaeological studies. In this pilot study, archaeological human remains from two Iron Age cemeteries (7th-twelfth centuries AD), Lejasbiteni and Cunkani-Drengeri, which are located in different regions of Latvia, were studied. We applied ancient DNA (aDNA) and tooth enamel peptide analysis to determine the biological sex of the individuals. In addition, aDNA analysis was used to perform mtDNA haplogroup analysis. In most cases, the results of aDNA analysis regarding the biological sex of individuals coincided with the gender assigned based on grave orientation and grave goods. The results of sex determination using peptide analysis in all four individuals for whom data were available matched the possible gender. Of the 17 samples that had sufficient DNA for sequencing, seven samples had enough reads to perform mtDNA haplogroup analysis. The H2a2a, I4a1, H2a2a1, and H16c mtDNA haplogroups were identified in the individuals from the Lejasbiteni cemetery, while the T2b and K1a + 150 mtDNA haplogroups were identified in the individuals from the Cunkani-Drengeri cemetery. Overall, the obtained results demonstrated the feasibility of applying aDNA and tooth enamel peptide analysis for biological sex determination within archaeological studies. The availability of human aDNA data will be highly useful for investigating the demographic history and social structures in Iron Age Latvia.