R577X polymorphism of alpha-actinin-3 in human populations of North-Eastern Asia

Abstract

Background. In polymorphism rs1815739, a C → T transition converts arginine to a premature stop-codon at residue 577 of the alpha-actinin-3 (ACTN3) protein (R577X polymorphism). This polymorphism may affect muscle performance, and the derived 577X allele has been found to be under-represented in sprint/power athletes. In addition, loss of alpha-actinin-3 results in a shift in muscle metabolism toward the more efficient aerobic pathway, thus pointing that this polymorphism may have been involved in enhancing the capability for hunting and for cold adaptation. Here, we study rs1815739 polymorphism in native populations (Chukchi, Koryaks and Evens) and newcomers (Russians) of North-Eastern Asia. Materials and methods. Genomic DNA was isolated from peripheral blood. ACTN3 genotypes for rs1815739 locus were established by enzymatic digestion of amplicons with DdeI. Heterozygotes TT were confirmed by DNA sequencing. In addition, data on exome variation in Siberian populations were analyzed. Results. Lowered frequencies (less than 40%) of “mutant” allele rs1815739-T were found in studied populations of North-Eastern Asia. Analysis of exome data has shown that haplotype comprising the rs1815739-T allele reaches the highest frequencies in populations of Southern and Central Siberia, while it is rather rare in the north-east of Siberia. Conclusion. The results obtained contradict the hypothesis that the rs1815739 polymorphism may have been involved in cold adaptation of North-East Siberians.