维生素D受体基因ApaⅠ多态性与男性骨量的关系

目的了解维生素D受体(vitaminDreceptor,VDR)基因ApaⅠ多态性与男性骨量的关系。方法PCR-限制性片段长度多态性技术检测上海市388例健康汉族男性VDR基因ApaⅠ多态性,并用双能X线吸收仪检查上述人群腰椎1～4(L1～4)和股骨近端股骨颈(Neck)、大转子区(Troch)及Ward's三角部位骨密度(bonemineraldensity,BMD)和骨矿含量(bonemineralcontent,BMC)。结果ApaⅠ多态性等位基因频率分布符合Hardy-Weinberg定律,基因型频率分布依次为aa(48.1%)、Aa(44.2%)和AA(7.7%)。协方差分析显示,在所有388例受试者中和160例60岁及以下亚组中,ApaⅠ基因型与L1～4和股骨近端各部位BMD、BMC值均无相关性;在228例60岁以上亚组中,ApaⅠ基因型与L1～4、Neck和Ward's三角部位BMD、BMC值均相关(P<0.05,P<0.01),AA基因型平均BMD、BMC值高于Aa和aa基因型(P<0.05,P<0.01),但是ApaⅠ基因型与Troch部位BMD和BMC值无相关性。结论VDR基因ApaⅠ多态性与60岁以上男性骨量相关,AA基因型具有较高的骨量,提示ApaⅠ多态性可能影响老年男性的松质和皮质骨骨量的丢失。

Association of Apa I polymorphism of vitamin D receptor gene with bone mass in men

OBJECTIVE: To investigate the association of Apa I polymorphism in vitamin D receptor (VDR) gene with bone mass in men. METHODS: The VDR Apa I genotype was determined by PCR-restriction fragment length polymorphism (RFLP) in 388 unrelated healthy men aged 46-80 years of Han nationality in Shanghai city. Bone mineral density (BMD) and bone mineral content (BMC) at lumber spine 1-4 (L1-4) and at any sites of proximal femur including to femoral neck (Neck), trochanter (Troch) and Ward's striangle (Ward's) were measured by duel-energy X-ray absorptiometry. RESULTS: Frequencies distribution of VDR Apa I genotype were aa for 48.1%, Aa for 44.2% and AA 7.7%. The allele frequencies of Apa I polymorphism were in Hardy-Weinberg equilibrium. No significant association was found between Apa I genotype and BMD or BMC in group of all population or in subgroup of men below 60 years. In men above 60 years, the significant association was found between VDR Apa I genotype and BMD or BMC at L1-4, Neck and Ward's (P < 0.05, P < 0.01) and compared with Aa and aa genotype, AA genotype had significantly higher mean BMD and BMC at L1-4, Neck and Ward's (P < 0.05, P < 0.01). But Apa I genotype is not associated with BMD and BMC at Troch. CONCLUSIONS: Apa I polymorphism is associated with bone mass in men above 60 years, and AA genotype has higher bone mass. Apa I polymorphism in VDR gene possibly influence loss of trabecular and cortical bone mass in old men.