Demand for larger Y-STR reference databases in ethnic melting-pot countries: Argentina as a test case.

The Y chromosome behaves as a single locus. Its genetic information is useful in forensic casework, deficiency kinship testing, and population genetics studies. Continuous increases of loci number within commercial kits forced modification of worldwide reference databases. In Pan American countries, like Argentina, diverse parental ethnic groups contributed to the extant admixed urban populations. We report 509 additional haplotypes of 23 Y-STRs from donors inhabiting urban areas of six Argentinean provinces: Buenos Aires, Santiago del Estero, Santa Cruz, Rio Negro, Santa Fe, and Formosa. To better understand the demographic landscape of the admixed urban paternal lineages, structural analysis was performed using published data from other Argentinean provinces. AMOVA by Rst distance and inferred haplogroups by two predictive online software methods based on haplotypes yielded complementary results with respect to detected population structure, probably due to the different proportions of the Native American Q3-M3 haplogroup in the studied samples. This situation, which is common to most North, Meso, and South American countries, underscores the need for the additional step of typing specific SNPs for haplogroup diagnosis. We propose organizing Y-STR haplotype reference databases according to the most frequent haplogroups detected in a given admixed population.