Аннотация:In order to be digested, the disaccharide trehalose needs to be cleaved by the enzyme known as trehalase. Trehalase deficiency is difficult to diagnose, and so information about its prevalence was scarce in the past; still, there were reports suggesting that this condition was more common in high-latitude populations than in the temperate climate zone. New horizons were opened for the epidemiologic research of trehalase enzymopathy when it became clear that reduced trehalase activity is determined by the A allele of the trehalase gene (rs2276064 TREH).The aim of this study was to analyze the frequencies of the trehalase gene alleles and genotypes among the indigenous peoples of Siberia and the Russian Far East. We genotyped 567 samples representing the small-numbered indigenous peoples of Siberia and the Russian Far East and 146 samples representing Eastern Slavs that formed the reference dataset. We found that the frequencies of the A*TREH alleles increased to the east. The frequency of the A*TREH allele was 0.03 in the reference group, 0.13 in the Khanty and Mansi populations of North-West Siberia and 0.26 in the Nenets populations. It was even higher in the populations of South Siberia (Shors, Tofalars, Tozhu Tuvinians: 0.29-0.30), West Siberian taiga (Evens and Evenks: 0.43) and the low Amur (Nanai: 0.46). The highest frequency of the A allele (0.63) was observed in the Far East in the Chukchi and Koryak populations.Our study shows that 1-5% of individuals of European origin are at risk of abdominal disorders caused by trehalase enzymopathy. The indigenous peoples of Siberia and the Russian Far East are at a substantially (by an order of magnitude) higher risk: in these populations, the frequency of the A*TREH allele responsible for reduced trehalase activity varies from 13% to 63%, whereas the frequency of the AA*TREH genotype varies from 3% to 39%. Thus, the total risk of trehalase enzymopathy among the homo- and heterozygous carriers of the A*TREH allele in the studied indigenous populations may be as high as 24% to 86%.
