Testing the informativeness of Y-STR and mitochondrial DNA control region markers in an attempt to predict ancestry of World War II victims from Slovenian mass grave.

Identification of human remains is a challenge in forensic genetics without relatives or personal items available. In Slovenia, a Konfin II mass grave from the Second World War (WWII) was found, containing skeletal remains of 65 victims. The archival documents detailing victims' information describe 45 persons of which 33 could be considered Germanic and 12 Slavic. This study aims to check for concordance between the victim list and actual victims found by using uniparental markers to differentiate between Slavic and non-Slavic origin by attempting to infer ancestry by analyzing the control region (CR) of mitochondrial DNA (mtDNA) and Y-chromosomal STRs. Diaphyses of femurs were used as a DNA source. Next Generation Sequencing (NGS) technology was used for mtDNA- namely HID Ion Chef™ Instrument, Precision ID mtDNA Control Region Panel, and Ion GeneStudio™ S5 System. For the Y-chromosome, PowerPlex^® Y23 System (Promega) kit and SeqStudio™ for human identification (HID) were used. European DNA Profiling mtDNA Population Database (EMPOP) and Y-Chromosome STR Haplotype Reference Database (YHRD) were searched for haplotype matches. Closest haplogroups were predicted using EMPOP, Y-DNA Haplogroup Predictor- NevGen, and Whit Athey's Haplogroup Predictor. Despite mitotypes being more diverse than Y-haplotypes, the Y-haplotypes had more database matches and more unequivocal differentiation between populations. 16 victims could be considered Slavic, 15 non-Slavic, and the remaining 34 had a rather scarce informativeness- either unclear or not providing any match. To address ancestry inference more comprehensively, analysis of autosomal ancestry informative markers as well as expansion on haploid markers will be conducted in future research.