Evaluation of the percentage of rs1695 polymorphism of GSTP1 gene in Iranian population in breast cancer

Introduction & Aim: Pharmacogenetics is the study of inherited differences in response to drug among different people.GSTP1 gene has positive effect on metabolism of cyclophosphamide and is effective for drug consumer. Patients with hetrozygous or homozygous mutants for the polymorphism are not at the risk of cyclophosphamide toxicity. This study showed a little high prevalence of rs1695 hetrozygous form in different ethnic groups of Iran. Our purpose is evaluation of rs1695 polymorphism frequency among 300 Iranian people with different ethnicities in order to use appropriate doses of cyclophosphamide by using pharmacogenetic tests. Methods: blood sample of 300 healthy people with different ethnicities include persian, azeri,kurd,baluch ,mazen and gilak were collected. After DNA extraction, presence or absence of polymorphism in the gene was analyzed using techniques: Tetra-ARMS PCR Results: In this study the frequencies of A allele which involves in drug effectiveness were also reportedas followes: Persian %60,Azeri %52,mazens%53,baluchis%72,Gilakis %50 and Kurd%57. According to this study there is a significant relationship (p<0/05) between genotype and allelic frequencies in Iranian population and cyclophosphamide administration. Thus, according to this information, the presence of these genotypes and A allele should be analysed before administering cyclophosphamide using pharmacogenetic tests in Iranian breast cancer patients as well as other asian countries in order to use standard dose of it in the presence of A allele. Conclusion: according to studies, its found that the presence of the homozygous allele(A/A) and in rs1695 polymorphic region of GSTP1,can neutralize several anti cancer drugs such as cyclophosphamide by toxic effects of this drug is not observable in patients carrying the A allele.