Association of HLA Class II Alleles (DRB1 and DQB1) in Iraqi Women with Endometriosis

Endometriosis is a chronic gynecological disease manifested by the occurrence of ectopic foci of endometrial tissue in the pelvic cavity and/or ovary. Etiopathogenesis of the disease is still poorly understood but there is a growing bulk of evidence that genetic factors and immunological abnormalities play a role in this disease. This study was performed to investigate the association of human leukocyte antigens class II genotypes (HLA-DR and DQ) with the susceptibility to endometriosis. Fifty female patients with endometriosis their age range (19 – 46) years and 30 females as control their ages were matched with the patients were enrolled in this study. Blood was collected from patients and controls, DNA was extracted from blood samples, and then HLA- genotyping was performed by polymerase chain reaction-sequence specific oligonucleotide probes (PCR-SSO). The present findings showed that DRB1*0307, DRB1*0701 and DQB1*0301 alleles were found with highly significant frequencies among patients (22 %; 34% and 24 %), in comparison with healthy control (0.0%) for three alleles, (P <0.001). On the other hand, it was observed that HLA-DRB1*0323 in high frequency among healthy individuals (23.3%) rather than in the patients (0.0%); with (P <0.001). This study demonstrates that HLA- DRB1*0307, DRB1*0701 and DQB1*0301 alleles may contribute to the increased susceptibility to endometriosis, whereas HLA-DRB1*0323 allele may confer protective effects against it, suggesting HLA-based different etiopathogenesis.