Objective: To investigate the association of polymorphism in estrogen receptor-alpha (ER-alpha ) gene with bone mineral density(BMD) in men.
Methods: The ER-alpha Xba I, Pvu II and Bst UI genotypes were determined by PCR-restriction fragment length polymorphism (RFLP) in 388 unrelated healthy men who were 46-80 years old and were of Han nationalities in Shanghai city. Bone mineral densities (BMD, g/cm(2)) at lumbar spines 1-4 (L(1-4)) and at any sites of proximal femur, including femoral neck (Neck), trochanter (Troch) and Ward's triangle (Ward's) were measured by duel-energy X-ray absorptiometry.
Results: The frequencies distribution of Xba I and Pvu II alleles and genotypes in this cohort all followed the Hardy-Weinberg equilibrium. No Bst UI polymorphic site in ER-alpha gene was found in total samples. All subjects were of BB genotype. No significant association was found between Xba I genotype and BMD at any skeleton sites. The significant association was found between Pvu II genotype and BMD at L(1-4) and Ward's triangle site (P< 0.05). Compared against men with PP and pp genotype, men with Pp genotype had significantly higher mean BMD at L(1-4) and Ward's triangle site (P< 0.05).
Conclusion: This study suggests that Bst UI polymorphism in ER-alpha gene may be absent or rare in Chinese Han population. Pvu II polymorphism possibly influences the loss of trabecular bone mass in old men.