[Polymorphism of estrogen receptor alpha genes Pvu I, Xba I and TA repeat sequence and hypomenorrhea with unknown aetiology].

OBJECTIVE: To study the roles of the polymorphism of the estrogen receptor genes in hypomenorrhea with unknown aetiology. METHODS: A case control study was carried out in south west of China, with 100 patients with hypomenorrhea in the case group and 100 eumenorrhea women in the control group. Molecular biology test was undertaken to test the restriction fragment length polymorphism (RFLP) of the first intron incision enzyme Pvu II, Xba I in ERa gene. Depuration, clone and sequence analysis was performed to the TA repeated sequence in the hypervariable region of estrogen receptor gene. The genotype distribution of ERa gene polymorphism was compard between the case and control groups. RESULTS: The patients with hypomennorrhea had higher P genotypic frequency (47.5%) than the control (30.5%), with an OR of 1. 810 (95% CI = 1.113-2.765, P = 0.012). The patients with hypomennorrhea had lower X genotypic frequency (20.5%) than the control (32.0%), with an OR of 0.641 (95% CI = 0.361-0. 898, P = 0.036). The patients with hypomennorrhea had higher frequency of TA13 allele (P = 0.006) and lower Frequency of TA15 allele frequency (P = 0.033) than the control. CONCLUSION: ERa gene polymorphism is associated with hypomenorrhea with unknown aetiology. P allele and TA13 allele may be risk factors, while X allele and TA15 allele may be protective factors.