AB048. X-chromosomal SNPs variation in populations of Russia

Abstract: X-chromosome markers are informative tool for studying a genetic diversity in human populations and have become a useful in DNA identification when certain complex kinship cases need to be unravelled. In this work we present population genetic data on X-chromosome-wide SNPs in North Eurasian populations and report XSNP multiplex system for forensic genetics. A total of 2,867 X-chromosomal SNPs were genotyped in 12 populations using Illumina microarray platform. Twelve populations under study (Komi, Mordva, Russians, Kirghiz, Kazakh, Uzbek, Buryat, Yakut, Evenk, Tuva, Khanty, Ket) represent various language families and geographic regions of North Eurasia (Eastern Europe, Central Asia, Siberia and North Asia). North Eurasian populations are highly genetically differentiated with respect to XSNPs allele frequencies. Average level of genetic differentiation (Gst) for 12 populations is 6.03% and ranged from 1.05% to 30.05% per individual SNP. Principal component analysis of allele frequencies demonstrated geographic pattern of population clustering, as well as longitudinal gradient in genetic diversity. The 66 XSNPs characterized by high expected heterozygosity and linkage equilibrium in populations under study were selected for constructing a panel for forensic genetic applications. Average heterozygosity of selected SNPs varied from 0.4925 to 0.4958. Overall values of power of discrimination for males and females (PDm and PDf) obtained with these XSNPs set are several magnitude higher than those for standard forensic STR panels. Protocol for multiplex amplification of 66 XSNPs in two separate multiplex PCR reactions and MALDI-TOF mass spectrometry genotyping was developed. North Eurasian populations demonstrate high level of genetic diversity and differentiation for X-chromosome-wide SNPs. Based on obtained population genetic data, highly informative multiplex XSNPs panel for forensic genetics was developed.

Keywords: Genetic diversity; X-chromosome SNPs; population genetics; forensic genetics