Своеобразие субэтнических групп ненцев по генетическим детерминантам метаболизма сахарозы, трегалозы и лактозы

Abstract

Introduction. The diet of indigenous northerners is changing significantly on account of the rapid growth in volume and variety of consummated food sugars. Concurrently, an arrow of northern aboriginal groups are known to have an increased percentage of genetically determined disorders of disaccharide metabolism. The study aimed to assess the polymorphism of genes and alleles that determine production or activity of sucrase-isomaltase, trehalase and lactase enzymes in the groups of Nenets of Western Siberia and European Arctic. Materials and methods. The genotyping of the samples of biomaterial from 236 unrelated individuals formed the basis of the study. We analyzed the genotype and allele frequencies of the SI (rs781470490), TREH (rs2276064) and LCT (rs4988235) genes in the groups of Forest, Gydan, Yamal and European Tundra Nenets. Results. There were not a single sample with the AG dinucleotide deletion at the rs781470490 locus of the sucrase-isomaltase gene (SI gene) found. The TREH allele distributions appeared to be extremely close in all the sub-ethnic groups of Nenets. The frequency of the associated with trehalase deficiency A*TREH allele in the Nenets groups is at 0.25-0.26, which is significantly higher than in the non-arctic populations of Russia (0.01-0.06). We have confirmed a high prevalence in the Nenets populations of the CC*LCT variant of the lactase gene, which determines the limited production of the enzyme. The frequencies of the genotype vary in the Nenets sub-groups from 0.90 in the Gydan and European Tundra Nenets to 0.70 in the Forest (the difference from the European Tundra group is significant at the level of p = 0.06) and 0.65 in the Yamal Nenets (significantly differ from both the Gydan and European Tundra groups, p < 0.05). Conclusion. The difference in metabolism-related gene complexes can be found not only between peoples, but even between sub-ethnic groups.