ESR2 and gallbladder carcinoma: Table 3 shows the risk of gallbladder carcinoma and stones in relation to each of the SNPs of ESR1, ESR2 and PGR. On comparing the genotype frequency distribution of our study groups i.e. GBC and gallstone patients with that of controls, the homozygous variant genotypes of ESR1 IVS1-397C>T (rs2234693) polymorphism showed statistically significant increased risk for developing GBC (p = 0.02; [OR], 1.8) and gallstone (p = <0.001; [OR], 2.9).