Intron 1 and exon 1 alpha estrogen receptor gene polymorphisms in women with endometriosis

ObjectiveTo evaluate the association of intron 1 and exon 1 polymorphisms in the estrogen receptor α gene (ER-α) with endometriosis in women.DesignAssociation study.SettingEndometriosis Unit, Federal University of São Paulo.Patient(s)The control group consisted of volunteers older than 45 years who had no evidence of endometriosis antecedents. Two groups with the disease were evaluated: the first group had stage I or II endometriosis and the second group stage III or IV.Intervention(s)Polymerase chain reaction (PCR) followed by digestion with HaeIII and MspI endonucleases (RFLP) were applied to detect intron 1 and exon 1 polymorphisms, respectively, in a total of 125 controls and 105 affected women.Main Outcome Measure(s)Frequency and distribution of HaeIII and MspI polymorphisms in ER-α.Result(s)No significant differences in the frequency of polymorphisms either in intron 1 or exon 1 of ER-α were found when endometriosis patients were compared with control subjects. Furthermore, the frequency of ER-α polymorphisms within the two different groups of patients with disease was statistically similar. The odds ratio between presence of intron 1 single-nucleotide polymorphisms (SNP) and endometriosis was 0.904, and the odds ratio between exon 1 SNP and endometriosis was 0.976.Conclusion(s)The evaluated polymorphisms were not associated with endometriosis.