GENOTYPE AND ALLELE FREQUENCIES OF N‐ACETYLTRANSFERASE 2 AND GLUTATHIONE S‐TRANSFERASE IN THE IRANIAN POPULATION

Abstract

1. Xenobiotic-metabolizing enzymes constitute an important line of defence against a variety of carcinogens. Many are polymorphic, constituting the basis for the wide interindividual variation in metabolic capacity and possibly a source of variation in the susceptibility to chemical-induced carcinogenesis. The aim of the present study was to determine the frequencies of important allelic variants in the N-acetyltransferase 2 (NAT2) and glutathione S-transferase (GST) genes in the Iranian population and compare them with frequencies in other ethnic populations. 2. Genotyping was performed in a total of 229 unrelated healthy subjects (119 men, 110 women) for NAT2 and 170 unrelated healthy subjects (89 men, 81 women) for GST from the general Tehran population. A combination of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) was applied for typing of NAT2 polymorphisms. Detection of GSTM1 and GSTT1 null alleles was performed simultaneously using a multiplex PCR assay. 3. The frequencies of specific NAT2 alleles were 0.299, 0.314, 0.380, 0.007 and 0.000 for 4 (wild-type), 5 (C481T, M1), 6 (G590A, M2), 7 (G857A, M3) and 14 (G191A, M4), respectively. The most prevalent genotypes were NAT2 5/6 (29.70%) and 4/6 (21.40%). The GSTM1- and GSTT1-null alleles were detected in 44.7 and 21.2% of subjects, respectively. 4. We found that Iranians resemble Indians with regard to allelic frequencies of the tested variants of NAT2. The predominance of slow (49.36%) and intermediate (41.47%) acetylation status compared with wild-type rapid acetylation status (9.17%) in the study group suggests the significant prevalence of the slow acetylator (SA) phenotypes in the Iranian population. Our data confirmed that Iranians are similar to other Caucasian populations in the frequency of both GSTM1- and GSTT1-null alleles.

Genetic Polymorphism of the Glutathione S-Transferase M1 and T1 Genes in Three Distinct Arab Populations

“…The prevalence of GSTM1 homozygous deficiency seen here was comparable for Europeans, including British (54%) [10,20], French (51%) [21], German (52%) [22] and Austrians (49%) [23]. In addition, they were comparable to Asians, such as Turkish (51.9%) [24], Iranians (44.7%) [25], Chinese (56.5%) [26], Koreans Fig. 1.…”

“…Worldwide differences in GSTT1 frequencies were previously documented [10,12], with 20% of Caucasians, 60% of Asians and 40% of Africans not expressing the GSTT1 enzyme [5]. The frequencies of GSTT1 deletion in our populations were higher than that described for Europeans, including British (18%) [20], French (16%) [21], German (13%) [22] and Austrian (20%) [23], as well as for other Middle Eastern populations, including Turks (17.3%) [24], and Iranians (21.2%) [25], but was significantly lower than SouthEast Asians, such as Chinese (56.5%) [26], Koreans (53.8%) [27] and Japanese (44%) [28]. The frequencies of GSTT1 null genotype in our Arab populations are similar to that of the sub-Saharan Africans: Zimbabweans (26%) [30], Gambians (37.1%) [31], Cameroonians (46.8%) [32] and Ivory Coast (33.1%) [33] (Table 2).…”

Study of NAT2 Gene Polymorphisms in an Indian Population

“…In the Iranian population, NAT2 * 6 was the most predominant allele followed by NAT2 * 5 and NAT2 * 4, which were similar. [41] In our current study, in which we tested for nine major SNPs, 15 different alleles were detected (table II). NAT2 * 5 was the major allele (37.2%) followed by NAT2 * 6 and wild type NAT2 * 4.…”

Interaction between glutathione-S-transferase polymorphisms, smoking habit, and HPV infection in cervical cancer risk

“…Table 1 shows the distribution and the related frequencies of GSTs genotypes in cases and controls entirely, and in the different subgroups (smokers and non-smokers). The H-W Ruzzo et al 2006;Torkaman-Boutorabi et al 2007). As reported in Table 2, smoking habit, considered alone, was not found to be a risk factor for cervical lesions (CLs) (OR = 1.16, 95% CI 0.59-2.27).…”