Frequency of NAT2 and GSTP1 polymorphisms in the Kazakh population

Abstract

Introduction: Phase II xenobiotic biotransformation enzymes perform detoxification of hydrophilic and often toxic Phase I products by glutathionetransferase (GST), UDP-glucuronosyltransferase (UDF), N-acetyltransferase (NAT) families and other enzymes. GST protein family metabolizes a large number of electrophilic xenobiotics, including drugs, by conjugating them with glutathione. Arylamine-N-acetyltransferase (NAT) catalyzes the acetylation of the aromatic and heterocyclic amines. Materials and methods: The current study has assessed the frequencies of NAT2 and GSTP1 genes polymorphisms in 326 healthy individuals from different regions of Kazakhstan by using Real-Time PCR and direct sequencing methods. Results: Allele frequencies were derived for NAT2*5 (0.54) and GSTP1 (0.27). GSTP1 alleles were in Hardy – Weinberg equilibrium (p > 0.05), while NAT2*5 (p = 0.00) were not. The population differences between North, Northeast and South Kazakhstan regions were determined. Statistically significant differences in the frequency of genotypes were not found. Conclusion: Allelic polymorphisms of NAT2*5 and GSTP1 genes vary widely in different populations. Kazakh population was significantly different from Asian, Caucasoid, African-American and Hispanic ones by NAT2*5 and GSTP1 genes. Allelic variants of the NAT2*5 were detected with a low frequency in Asian populations. Allelic frequency in other world populations varies from 30 to 50%. The differences between Kazakh (0.54) and the world population were statistically significant (p < 0.05). The frequency of GSTP1 (rs1695) in the African American population is 42%. The frequency of GSTP1 in Asian populations varies from 11% to 23%, in Caucasoid populations it is about 30%. The differences between Kazakh population (0.27) and other populations selected from the literature were statistically significant (p < 0.05). The study of mutations in GSTP1 and NAT2 genes is necessary to assess the risk of the development of various diseases, such as cancer. Information on allelic polymorphisms also might be useful for personalized drug prescription for such drugs as cyclophosphamide, cisplatin, methotrexate, isoniazid, pyrazinamide, and rifampin.