Endometriosis is a complex gynecological disorder, affecting up to 10% of women of childbearing age, characterized by the presence of functional endometrial tissue at ectopic positions generally within the peritoneum. It is a heritable condition influenced by multiple genetic, epigenetic and environmental factors, with an overall heritability estimated at approximately 50%. The aim of the present study was to evaluate the association of rs1250248 and rs11674184 single nucleotide polymorphisms (SNPs), mapping to fibronectin 1 (FN1) and growth regulation by estrogen in breast cancer 1 (GREB1) genetic loci, respectively, with the risk of endometriosis. A total of 166 women with endometriosis (stages I-IV) who were hospitalized for the condition, diagnosed by laparoscopic intervention and histologically confirmed, and 168 normal controls were recruited and genotyped. Genotyping of the rs1250248 and rs11674184 SNPs was performed with TaqMan primer/probe sets. A significant association was detected with the A allele, as well as the AA and AG genotypes of rs1250248 (FN1) in patients with endometriosis, as well as in patients with stage I and II of the disease only. The rs11674184 SNP of the GREB1 gene was not found to be associated with an increased susceptibility to endometriosis either for all patients (stages I-IV) or for subgroups of stage I and II or III and IV of the disease only. Our results demonstrated a genetic association between the rs1250248 (FN1) SNP and endometriosis at both the genotypic and allelic level. However, although rs11674184 of GREB1 constitutes one of the most consistently associated SNPs with endometriosis in European ancestry populations, it was not found to be associated with endometriosis in this study.
