Detection of single Nucleotide Polymorphism E326K of SHBG Gene in Breast Cancer of Iranian Females

Background & Objective: Sex Hormone-Binding Globulin (SHBG) is a plasma glycoprotein that regulates the action of steroid hormones on several levels. Since SHBG is one of the growth regulators of breast cancer cells, the aim of this study was to evaluate the association between polymorphisms E326K and the risk of breast cancer. Materials & Methods: This study was done as a case-control study on 79 patients with breast cancer and on 79 healthy women who had gone to Shohada-e Tajrish Hospital in Tehran. The average age of patients and control subjects were 48 -+ 8 and 43 -+ 6 years, respectively. After blood sampling and DNA extraction, genotyping of all samples were determined by PCR-RFLP method and the results were statistically analyzed using SPSS 19 software. Results: After counting the genotypes, their percentages in the cancerous specimens and control group were AA (56.9%), GG (35.4%), AG / GA (7.6%) and AA (12.6%), GG (77.2%), AG / GA (10.1%), respectively. In addition, according to Hardy-Weinberg equilibrium, in cancer patients, the frequency of allele A was 60.7% and the frequency of allele G was 39.2% and in control group the frequency of allele A was approximately 21.5% and the frequency of allele G was calculated 82.3%. Statistically, a significant correlation was observed between the homozygotes of the two groups (P-Value ˂0.05). Conclusion: The results showed that the E326K polymorphism in exon 8 of SHBG gene is associated with the risk of breast cancer and it may be a factor involved in it.