Polymorphisms in the estrogen receptor beta gene but not estrogen receptor alpha gene affect the risk of developing endometriosis in a Japanese population.

OBJECTIVE: To determine whether polymorphisms in the estrogen receptor (ER) alpha and beta genes are associated with endometriosis in a Japanese population. DESIGN: Association study. SETTING: University hospital. PATIENT(S): Japanese women diagnosed with endometriosis by laparotomy or laparoscopy. INTERVENTION(S): Determination of polymorphisms in the ERalpha and ERbeta genes was performed by polymerase chain reaction restriction fragment-length polymorphism analysis in 132 affected women and 182 controls. MAIN OUTCOME MEASURE(S): Frequency and distribution of AluI and RsaI polymorphisms in ERbeta gene and of PvuII and XbaI polymorphisms in ERalpha gene. RESULT(S): No significant differences in the frequency of either AluI and RsaI polymorphisms in the ERbeta gene or of XbaI and PvuII polymorphisms in the ERalpha gene were found between endometriosis patients and controls. However, a positive association was noted between the AluI polymorphism in the ERbeta gene and stage IV endometriosis patients in the population studied. CONCLUSION(S): The AluI polymorphism in the ERbeta gene is associated with an increased risk of stage IV endometriosis in a Japanese population.