Association of Xba I , Pvu II, and Bst U I polymorphisms of estrogen receptor-α gene with bone mass in men

Objective: To investigate the association of polymorphism in estrogen receptor-α (ER-α) gene with bone mineral density(BMD) in men. Methods: The ER-α Xba I, Pvu II and BstU I 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/cm²) 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 BstU I polymorphic site in ER-α 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 BstU I polymorphism in ER-α gene may be absent or rare in Chinese Han population. Pvu II polymorphism possibly influences the loss of trabecular bone mass in old men.