雌激素受体α基因XbaⅠ、PvuⅡ和BstUⅠ多态性与男性骨量的关系

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

目的了解雌激素受体α(estrogenreceptorα,ERα)基因多态性与男性骨密度(bonemineraldensity,BMD)的关系。方法PCR限制性片段长度多态性检测上海市388名46～80岁无血缘关系的健康汉族男性ERα基因XbaⅠ、PvuⅡ和BstUⅠ多态性,双能X线吸收仪检查腰椎1～4(L1～4)和股骨近端股骨颈(femoralneck)、大转子区(trochanter)和Ward’s三角部位BMD。结果被研究人群XbaⅠ和PvuⅡ等位基因频率分布符合HardyWeinberg定律。未发现ERα基因第1外显子区存在BstUⅠ多态性,所有对象均是BB基因型。XbaⅠ多态性与各部位BMD值均无相关;PvuⅡ多态性与L1～4和Ward’s三角部位BMD值均有关联(P<0.05),Pp基因型在上述部位平均BMD值明显高于PP和pp基因型(P<0.05)。结论本研究结果提示中国汉族人群缺乏或罕有ERα基因BstUⅠ多态性;ERα基因PvuⅡ多态性可能影响老年男性松质骨骨量的丢失。

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 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 （L1-4） 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 α genotype and BMD at any skeleton sites. The significant association was found between Pvu Ⅱ genotype and BMD at L1-4 and Ward＇s triangle site （P 〈 0.05）. Compared against men with PP and pp genotype, men with Pp genotype had significantly higher mean BMI） at L1-4 and Ward＇ s triangle site （ P 〈 0.05 ）. Conclusion This study suggests that BstU Ⅰ polymoorphism 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.