Karkoszka H, Chudek J, Strzelczyk P, Wiecek A, Schmidt-Gayk H, Ritz E, Kokot F
Department of Nephrology, Endocrinology and Metabolic Diseases Silesian University School of Medicine, Katowice, Poland.
Nephrol Dial Transplant. 1998 Aug;13(8):2077-80. doi: 10.1093/ndt/13.8.2077.
It has been suggested that the vitamin D receptor (VDR) gene BsmI-polymorphism is a genetic determinant of bone metabolism.
To test this hypothesis, the relationship between VDR genotypes, bone mineral density (baseline and after 18 months) and parameters of calcium metabolism and bone turnover were investigated prospectively in 88 haemodialysed patients not receiving active vitamin D metabolites.
Whole body, lumbar spine and femoral neck bone mineral density (BMD) were assessed by dual energy X-ray absorptiometry (DEXA). In addition calcium, phosphorus, 25(OH)D3, 1,25(OH)2D3, osteocalcin serum concentrations, alkaline phosphatase activity and intact 1,84 PTH levels were measured.
VDR genotype BB, Bb and bb were found in 27, 49 and 24% of patients. Initial BMD (g/cm2) of whole body, lumbar spine and femoral neck did not differ between genotypes (whole body: BB 1.055 +/- 0.120, Bb 1.082 +/- 0.102, bb 1.128 +/- 0.120; lumbar spine: BB 1.075 +/- 0.199, Bb 1.079 +/- 0.185, bb 1.099 +/- 0.170; femoral neck: BB 0.808 +/- 0.160, Bb 0.862 +/- 0.127, bb 0.842 +/- 0.125; mean +/- SD), but the decrease of whole body and femoral neck BMD during 18 months was significantly (P < 0.02) different between the genotype groups (whole body: BB -0.048 +/- 0.028, Bb -0.031 +/- 0.029, bb -0.024 +/- 0.023; femoral neck BB -0.044 +/- 0.069, Bb -0.032 +/- 0.081, bb -0.012 +/- 0.029 g/cm2).
This preliminary study suggests faster mineral loss in BB genotype of VDR in haemodialysed patients.
有人提出维生素D受体（VDR）基因BsmI多态性是骨代谢的遗传决定因素。
为验证这一假设，对88例未接受活性维生素D代谢物治疗的血液透析患者，前瞻性研究了VDR基因型、骨密度（基线及18个月后）与钙代谢及骨转换参数之间的关系。
采用双能X线吸收法（DEXA）评估全身、腰椎和股骨颈的骨密度（BMD）。此外，还测量了钙、磷、25（OH）D3、1,25（OH）2D3、骨钙素血清浓度、碱性磷酸酶活性及完整的1,84甲状旁腺激素（PTH）水平。
患者中VDR基因型BB、Bb和bb的比例分别为27%、49%和24%。不同基因型患者全身、腰椎和股骨颈的初始骨密度（g/cm²）无差异（全身：BB 1.055±0.120，Bb 1.082±0.102，bb 1.128±0.120；腰椎：BB 1.075±0.199，Bb 1.079±0.185，bb 1.099±0.170；股骨颈：BB 0.808±0.160，Bb 0.862±0.127，bb 0.842±0.125；均值±标准差），但18个月期间全身和股骨颈骨密度的下降在基因型组间有显著差异（P<0.02）（全身：BB -0.048±0.028，Bb -0.031±0.029，bb -0.024±0.023；股骨颈BB -0.044±0.069，Bb -0.032±0.081，bb -0.012±0.029 g/cm²）。
这项初步研究表明血液透析患者中VDR基因BB基因型的矿物质流失更快。
