Endemic Opisthorchis Felineus Infection Limits Changes of Individual with Mutant Cyp1a1 and Gstm1 Genes to be Effectively Involved in Oil Field Working in the North of Siberia

More than 90% of the population of the north of Siberia (Russian Federation) inhabiting near oil field sites is infected with the endemic helminth of Opisthorchis felineus. We demonstrated that the oil industry workers with the length of service at oil fields more than ten years do not have homozygous mutant alleles of CYP1A1 and GSTM1 genes of xenobiotic biotransformation system. Moreover, opisthorchiasis infection induces among the workers with homozygous mutant alleles of the genes significant increase in the frequency of cytogenetical abnormal cells as well as the deterioration of their health. It has been found that the Opisthorchis felineus infected workers with mutant alleles of the genes generally fail to work effectively and are retired. The habit of smoking among the workers also significantly increased the frequency of micronucleated cells.