Polymorphism of apoptosis marker genes in the blood of indigenous people with gastric cancer in the Republic of Tyva

Introduction. Russia is among the leaders in incidence and mortality from gastric cancer (GC). The incidence of gastric cancer in the Republic of Tyva is especially abnormally high. Currently, there is interest in studying genetic factors in various types of cancer. But for GC, such research is not enough.Aim. To study the polymorphism of the apoptosis marker genes CASP9 (rs1052576), TP53 (rs1042522), FAS/APO-1 (rs2234767) in the blood of indigenous people with GC in the Republic of Tyva.Materials and methods. 107 Tuvinians were examined (47 people with GC and 60 persons in the control group). The diagnosis of GC was established on the basis of a comprehensive laboratory, instrumental and morphological examination by oncologists at the Republican Oncology Dispensary. Genotyping of polymorphisms rs1052576 CASP9, rs2234767 FAS/APO-1 and rs1042522 TP53 was carried out in all 47 patients with GC and in 60 people in the control group using the polymerase chain reaction method from DNA samples isolated from venous blood.Results. In patients with GC, compared with healthy individuals, the mutant allele G (44.7% versus 27.5%; p = 0.01) and the homozygous genotype GG (23.4% versus 6.7%; p = 0.03) of polymorphism rs1042522 TP53, as well as mutant allele A (57.4% versus 32.5%; p < 0.001) and homozygous genotype AA (31.9% versus 15.0%; p = 0.05) of polymorphism rs2234767 FAS/ APO-1 were more often registered among indigenous inhabitants of the Republic of Tyva. The frequency of various genotypes and alleles of the polymorphism rs1052576 CASP9 did not differ significantly between patients with GC and healthy individuals.Conclusion. Based on these results, it can be assumed that the A allele of rs2234767 FAS/APO-1 and the disruption of the anti-oncogenic function of the p53 protein produced by the G allele of rs1042522 TP53 are associated with GC and can be used as markers to determine increased risk in the population of indigenous residents of the Republic of Tyva.