Genetic contribution of the interferon gamma dinucleotide-repeat polymorphism in South Indian women with endometriosis
To investigate whether the interferon-gamma (IFNG) gene dinucleotide (CA)-repeat polymorphism is responsible in part for genetic susceptibility to endometriosis in South Indian women.Following extraction of genomic DNA, genotyping of interferon-gamma CA-repeat polymorphism was performed using genescan technology.The global IFNG allele frequencies in all patients with endometriosis were significantly different from those in the control women (chi(2) = 37.062; 6 degrees of freedom; P < or = 0.0001). Significant difference was observed in global allele frequencies between the control women and each clinical subgroup of patients with endometriosis except for patients suffering from endometriosis associated with adenomyosis. The difference was due to an increase in a12 (112 bp) allele in the patients with endometriosis and each clinical subgroup of patients with endometriosis. The distribution of the IFNG a12 genotypes was significantly different between patients with endometriosis and the control women. (chi(2) = 10.635; 2 degrees of freedom; P = 0.0049). A significant difference in the IFNG a12 genotypes was found only among the three clinical subgroups.These results suggest that the IFNG gene CA-repeat polymorphism is associated with susceptibility to endometriosis in South Indian women.