The variability of potentially important functional polymorphic variants rs2069705 (5'UTR of the IFNG gene), rs17880053 (near 5'UTR of the IFNGR2), rs11126176 (LOC100287361 pseudogene), and rs804271 (near 5'UTR of the NEIL2 gene) was characterized in representatives of four ethnic groups living in the Siberian region. These ethnic groups included three indigenous Mongoloid ethnic groups (Yakuts, the residents of the Republic of Sakha (Yakutia), Tuvinians from the Republic of Tuva, and Buryats from the Republic Buryatia) and the alien Russian population. All of the examined variants were polymorphic. The frequency of the rs2069705 allele C in Russians was 0.5833, while it was in a range from 0.7842 to 0.8967 in representatives of the indigenous populations. The frequency of rs17880053 deletion was 0.8073 in Russians and from 0.4474 to 0.5521 in the indigenous ethnic groups. The frequency of the rs11126176 allele A was equal to 0.5398 in Russians but was recorded with lower frequencies in indigenous ethnic groups (from 0.2722 to 0.4551). The frequency of the rs804271 allele Gwas 0.5215 in Russians and from 0.2527 to 0.4022 indigenous ethnic groups. With respect to the genotype structure, the alien Russian population was considerably distanced from indigenous Mongoloid populations. Specifically, the genetic distance was 0.0742 between Russians and Yakuts, 0.1365 between Russians and Tuvinians, and 0.1433 between Russians and Buryats. Among the Mongoloid indigenous ethnic groups of Siberia, Tuvinians and Yakuts were the most distant from each other (0.0262). The genetic distance was equal to 0.0151 between Yakuts and Buryats and 0.0127 between Buryats and Tuvinians.