北京地区汉族青年女性钙敏感受体基因多态性分布及其与骨密度相关性的研究

目的了解北京地区汉族青年女性钙敏感受体（Calcium-sensing ReceptOF，CaSR）基因多态性的分布，探索其与汉族妇女峰值骨密度的相关性。方法分别采用突变分离PCR和错配PCR-RFLP方法检测北京地区202名无亲缘关系的汉族青年健康女性（20～35岁）受试者CaSR基因A986S、G990R基因型，测定其血钙（Ca）、磷（P）及甲状旁腺素（PTH）水平，以及肝肾功能等指标，应用双能X线骨密度仪（DXA）测定腰椎、股骨上段部位的骨密度（BMD）。结果（1）北京地区汉族女性中存在CaSR基因A986S、G990R多态性，AA、AS基因型频率分别为95．0％和5．0％，等位基因A和s的频率分别为97．5％和2．5％；RR、GR及GG基因型频率分别为21．3％、51．0％和27．7％，等位基因R和G的频率分别为46．8％和53．2％。（2）校正年龄、身高、体重、BMI及血Ca、PTH水平后，多因素协方差分析显示AA、AS基因型组之间L2-4、股骨颈、ward＇s三角及大转子部位的BMD无显著差异（P=0J090～0．671）；GG、GR及RR基因型组之间L2。、股骨颈、ward＇s三角及大转子部位的BMD也无显著差异（P=0．089～0．493）。结论（1）北京地区汉族青年女性中CaSR基因A986S、G990R多态性的分布频率，以A、G等位基因频率较高。（2）未发现CaSR基因A986S、G990R多态性与北京地区汉族青年女性峰值骨密度相关。

Association of calcium-sensing receptor gene polymorphism with bone mineral density in healthy young women of Hem nationality in Beijing area

Objectives To investigate the distribution of CaSR gene polymorphisms in healthy young women of Han nationality in Beijing area and to explore the association of CaSR genotypes and peak bone mineral density in healthy women. Methods 202 healthy young women aged 27 ± 5 years of Han nationality in Beijing area were recruited in this study. Whole blood genome DNA was extracted by QIAGEN DNA extraction kit. A986S and G990R genotypes were determined by mutagenically seperated polymerase chain reaction （MS-PCR） and PCR-RFLP, respectively. Serum calcium, albumin, phosphorus, PTH were measured. BMD of lumbar spine （ L2-4 ） and proximal femurs was measured by DXA. Results （ 1 ） There were A986S and G990R polymorphisms in healthy young women of Han nationality in Beijing. The frequencies of genotypes were as follows： no SS, AA 95.0% and AS 5.0% for A986S, RR21.3%, GR.51.0% and GG27. 7% for G990R. Hardy-Weinberg equilibrium was evident. （2） No differences of BMD at L2-4, neck, ward＇s triangle and trochanter were found among different genotypes after adjusting for age, height, weight, BMI and serum Ca, P, PTH. Conclusion There were A986S and G990R polymorphisms in CaSR gene in Han nationality in Beijing area. A and G allele were more common. It was indicated that the distribution of CaSR gene polymorphisms in Chinese was different from that in Caucasians. No correlation between A986S or G990R polymorphisms and peak BMD was observed in young women of Han nationality in Beijing area.