Study of regulatory promoter polymorphism (-248 G>A) of Bax gene in patients with gastric cancer in the northern provinces of Iran

AIM The aim of this study is to evaluate the polymorphism in Bax gene and its association with some clinical pathology traits in gastric cancer. BACKGROUND Gastric cancer is considered as the fourth most common cancer in the north and northwest of Iran. Bcl2 family has a key role in regulation of apoptosis, and any changes in the expression of Bcl2 lead to cancer. PATIENTS AND METHODS Blood samples were collected from 100 cases and 89 controls in the northern provinces of Iran to evaluate promoter polymorphism (-248G<A) of Bax gene. Genotyping was carried out by PCR-RFLP method. RESULTS The result of this study demonstrated the existence of polymorphism in the above-mentioned region of Bax gene. Sixty-nine patients (%69) with genotype GG and 31 patients (%31) with genotype AG were observed in the case group. No mutant genotype was found among cases. Sixty-seven individuals (%75/28) with genotype GG, 21 individuals (%23/59) with genotype AG and only one mutant genotype (AA) were demonstrated in the control group. The bioinformatics analysis showed that this polymorphism removed the probable Sp1 motifs, which may affect its expression in the cells. CONCLUSION Allele G was the most frequent between both patient and control samples. Polymorphism may be effective on Bax expression, but it requires further investigation. Our results showed significant effects between genotypes and features of gender and age, whereas no significant relation were observed between the genotypes and grade, stage as well as smoking traits.