High degree of Y-chromosomal divergence within Finland—forensic aspects

Among the Finns, the levels of autosomal STR and mtDNA variation have been reported to be relatively high and evenly distributed throughout the country. In contrast, the Y-STR variation is markedly lower than observed in most other European populations, showing notable geographical substructure within Finland. There are striking interregional differences—the western, middle and eastern parts of Finland segregate clearly, with ΦST values comparable to the highest divergences among European populations. The low Y-STR diversity reduces the discriminative power of Y-chromosomal markers among Finns, and, furthermore, the geographical substructure complicates the assessment of profile probabilities in forensic settings. Here, the Y-STR diversity pattern in Finland is for the first time evaluated from the forensic viewpoint.