Reduced-volume and low-volume typing of Y-chromosomal SNPs to obtain Finnish Y-chromosomal compound haplotypes.

Single-nucleotide extension is a widespread method for typing Y-chromosomal single-nucleotide polymorphisms. In our study, we validated a multiplex minisequencing assay in a reduced-volume and in a low-volume approach. A four-plex assay was performed in a 6-microL multiplex reaction in 96-well microtiter reaction plates, which can be directly used for capillary electrophoresis. In a second approach, a six-plex assay was performed on a chemically structured glass slide. Both techniques have proven to be highly sensitive as well as time- and cost-saving, which makes them a valuable option not only for forensic purposes but also for population genetic studies where large sample numbers have to be analyzed. In the present paper, both techniques are compared and applied to analyze a population sample from the area of Turku, Finland. The most common haplogroup was found to be N1c*, which is nearly absent in western and central European populations. Additionally, 11 short tandem repeat markers were analyzed to further discriminate Y-chromosomal lineages.