维生素D受体基因BsmⅠ多态性与北方汉族成人慢性肾功能不全骨密度的关系

The association of vitamin D receptor gene polymorphism and bone mineral density of patients with renal failure in Han Population in the northern China

目的:探讨维生素D受体(VDR)基因BsmⅠ位点多态性与北方汉族成人慢性肾功能不全骨密度的关系,探讨影响骨密度的遗传易感因素。方法:选取211名河北联合大学附属医院连续收治的汉族成人(年龄≥18岁)慢性肾功能不全患者并根据血肌酐(Scr)水平分为肾功能不全组和肾功能衰竭组,采用聚合酶链反应-限制性片段长度多态性分析(PCR-RFLP)的方法检测VDR基因BsmⅠ多态性位点,对慢性肾功能不全相关的因素进行问卷调查,同时检测入院24 h内肝肾功能、血钾、钠、氯、钙、磷、甲状腺功能、血甲状旁腺激素水平,及腰椎L2～4、颈椎、Wards三角部位骨密度。用Pearson相关分析进行年龄及体质指数(BMI)与骨密度关系的研究,用协方差分析的方法比较年龄、BMI校正后各部位骨密度与VDR基因型之间的关系。结果:肾功能不全组和肾功能衰竭组VDR基因BsmⅠ多态性分布无统计学意义(χ2=0.088,P=0.591)。年龄、BMI与骨密度的Pearson相关分析发现,年龄与各部位的骨密度呈负相关(P<0.01),BMI与骨密度值呈正相关(P<0.01)。采用协方差分析对年龄与BMI进行校正后,对不同部位的骨密度值与VDR基因型相关性进行分析,发现VDR不同基因型间腰椎的骨密度值差异有统计学意义(P<0.05),aa基因型具有较低骨密度(P<0.05)。结论:VDR基因BsmⅠ位点多态性与慢性肾功能不全患者骨密度存在关联,可能是影响骨密度的遗传易感因素。

Objective：To investigate the association between vitamin D receptor（VDR） gene polymorphism and the bone mineral density of the chronic renal failure patients in the northern China.Methods：A total of 211 patients with chronic renal failure coming from unrelated families in the northern China were selected.The subjects were divided into the chronic renal failure group（n=110） and the uremia group（n =101） by the level of serum creatinine.Polymerase chain reaction and restriction fragment length polymorphism（PCR-RFLP） was used to detect VDR Bsm Ⅰ polymorphisms.Information on environmental-related risk factors was collected using a pre-tested standard questionnaire.Bone mineral density was measured by dual energy X-way absorptiometry. Concentration of serum intact parathyroid hormone was measured by radioimmunoassay.Results：According to the χ 2 test,there was no significant difference between the chronic renal failure group and the uremia group（χ 2 = 0.088,P = 0.591）.Age had significant negative correlation with bone mineral density（P 0.01） while body mass index had significant positive correlation with bone mineral density（P 0.01）.Statistical differences of bone mineral density in lumbar were showed among different VDR genotypes（P 0.05）. People with aa genotype had significant lower bone mineral density in lumbar spine（P 0.05） after correcting the body mass index and age.Conclusion：The results show that there is a possible correlation between the polymorphisms of VDR gene BsmⅠand bone mineral density in chronic renal failure patients in the northern China.It indicates that the restriction site polymorphisms of BsmⅠ gene may be used as a genetic markers.