上海地区汉人维生素D受体基因多态性与骨密度关系的初步分析

目的：了解维生素D受体（VDR）基因多态性在中国人群中的分布，并进一步研究其与骨密度的关系。方法：通过聚合酶链反应－限制性片段长度多态性（PCR－RFLP）方法分析了348例无亲缘关系的上海地区男女居民的VDR基因型，并用双能X线吸收仪测定了其中202例骨密度。结果：348例研究对象中bb型占81．9％，Bb型占18．1％，未见到BB型。b等位基因在本组人群中分布 高达90．0％。男女性之间VDR基因型分布频率无明显区别（P＞0．5）。比较这两组各部位的骨密度值，只有女性在华氏三角区部位显示出Bb型比bb型有较高的BMD，在其余部位，不管男性还是女性，两组基因型的BMD均差异无显性（P＞0．05）。结论：VDR基因多态性与骨密度无相关关系。     

甲状旁腺素基因多态与2型糖尿病患者骨密度的关系

目的 探讨甲状旁腺素(PTH)基因多态与中国北方汉族人2型糖尿病患者骨密度的关系.方法 运用聚合酶链反应限制性片段长度多态性(PCR-RFLP)技术检测了2型糖尿病(T2DM)组104例,健康对照(CON)组102例,206例中国北方汉族人PTH基因多态性;采用双能X线吸收法骨密度仪(DEXA)测量骨密度(BMD).结果 甲状旁腺素(BSTB1位点)基因型和等位基因分布频率在2型糖尿病组与对照组间差异无显著性(P>0.05);在对照组及2型糖尿病组,Bb/bb基因型者L2-4和Neck部位BMD显著低于BB型(P<0.05),Troch及Wards三角区BMD差异无显著性(P>0.05).结论 2型糖尿病患者PTH基因多态性(BST B1位点)可能是预测骨量减少、骨质疏松易感性的遗传标志.     

维生素D受体等位基因多态性与骨密度相关性分析

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维生素D受体基因型与骨密度

目的考察维生素D受体(VDR)基因多态性在我国汉族人群中的分布频率,分析VDR基因型与骨密度的关系.方法采用聚合酶链反应和限制性酶切技术检测100例绝经前健康妇女VDR基因多态性.应用双能X线骨密度仪检测受试者腰椎及髋部骨密度.结果VDR基因型分布频率为BB型4.0%,Bb型10.0%,bb型86.0%;而三种基因型受试者髋部及腰椎骨密度均表现出Bb＞bb＞BB,经F检验腰椎骨密度3基因型比较,P＜0.05,具有显著差异.结论绝经前妇女VDR基因型分布频率与西方及国内的一些报道不尽相同,且骨密度显示出Bb＞bb＞BB,亦与国内外一些研究结果不同.     

维生素D受体基因多态性与原发性甲状旁腺功能亢进症的关系

目的 探讨维生素D受体（vitamin Dreceptor ,VDR)基因多态性与原发性甲状旁腺功能亢进症（primary hyperparathyroidism,PHPT)的关系。方法 应用多聚酶链反应法和限制性内切酶技术检测30例PHPT患者和60例正常对照组的VDR基因型。结果 VDR基因型在PHPT患者中的分布为BB型0例，Bb型1例（3．3％），bb型29例（96．7％）；正常对照组BB型2例（3．3％），Bb型11例（18．4％），bb型47例（78．3％）。PHPT患者与对照组BB，Bb,bb基因型分布差异有显著性（P≤0.05）。结论 PHPT与VDR基因多态性有一定关系。     

维生素D受体基因TaqⅠ多态性与绝经后妇女骨密度的关系

目的 了解福州地区绝经后妇女维生素D受体基因TaqⅠ多态性的分布,探讨维生素D受体基因TaqⅠ多态性与绝经后妇女骨密度的关系.方法 用双能X线骨密度仪检测592例绝经后妇女的腰椎、股骨颈、大转子和Wards三角骨密度,应用PCR-RFLP技术检测维生素D受体基因TaqⅠ多态性.结果 ①维生素D受体基因型分布频率为TT型90.37%,tt型0.17%,Tt型9.46%.等位基因频率为T 95.1%,t 4.9%,基因型分布符合Hardy-Weinberg定律.②分析其基因型与骨密度的关系:TT、tt、Tt 3种基因型在腰椎、股骨颈、大转子、Ward's区4个部位骨密度差异均无显著性.结论 维生素D受体基因TaqⅠ多态性与骨密度间无关联,不能作为预测福州地区绝经后妇女发生骨质疏松危险性的遗传标志.     

福州地区汉族老年男性维生素D受体基因多态性与骨密度的关系

目的 观察福州地区汉族老年男性维生素D受体(vitamin D receptor,VDR)基因BsmI,ApaI及TaqI多态性分布及与骨密度的关系.方法 选择福州地区60岁以上汉族男性150例,检测其正位第2-4腰椎、左侧股骨颈、大转子和Ward's区骨密度,应用聚合酶链式反应-限制性片段长度多态性(PCR-RFLP)检测维生素D受体基因BsmI,ApaI及TaqI多态性.结果 受试对象中,VDR BsmI基因型分别为BB型5例(占3.3%)、Bb型11例(占7.3%),bb型134例(占89.4%),b等位基因频率为93.0%、B等位基因频率为7.0%;ApaI基因型分别为AA型12例(占8.0%)、Aa型64例(占42.7%),aa型74例(占49.3%),A等位基因频率为29.3%、a等位基因频率为70.7%;TaqI基因型分别为TT型136例(占90.7%)、Tt型14例(占9.3%),无tt型,T等位基因频率为95.3%、t等位基因频率为4.7%.分析基因型与骨密度的关系显示:三个多态性位点各基因型人群在腰椎、股骨颈、大转子、Ward's区4个部位骨密度差异无统计学意义(P>0.05).结论 维生素D受体基因BsmI,ApaI及TaqI多态性与骨密度间没有关联,尚不能作为预测福州地区老年男性发生骨质疏松危险性的遗传标志.     

雌激素受体α和维生素D受体基因多态性与哈尔滨地区绝经后妇女骨密度的关系

目的探讨哈尔滨市绝经后妇女雌激素受体α(ER-α)基因和维生素D受体(VDR)基因多态性与骨密度的关系。方法对哈尔滨市81例无亲缘关系汉族健康妇女进行PCR-RFLP测定ER-α基因PvuⅡ、XbaⅠ多态性和VDR基因BSMⅠ多态性,用双能X线吸收法测定骨密度(BMD)。结果本研究人群PP、Pp及pp基因型频率分别为13.6%、49.4%、37.0%;XX、Xx及xx基因型频率各为4.9%、40.7%、54.4%;BB、Bb及bb基因型频率各为0%、16.0%、84.0%,t检验分析各基因型与BMD值的关系显示:绝经后妇女中,雌激素受体基因型仅与腰椎骨密度有显著差异。维生素D受体基因型在股骨颈、大转子部位有显著差异。PvuⅡ多态性和BSMⅠ多态性共同作用对骨密度影响更大。结论雌激素受体、维生素D受体基因型分布频率均符合Hardy-Weinberg定律,并且与骨密度有一定的关联,尤其是基因与基因的共同作用与骨密度的关系更为密切。     

维生素D受体基因Apal多态性与核心家庭女性峰值骨密度关系研究

目的 探讨维生素D受体（VDR）基因ApaⅠ多态性与中国核心家庭女性峰值骨密度（BMD）的关系。方法 收集上海市401个由汉族父母双亲和至少一个健康女儿（年龄在20～40岁）组成的核心家庭。运用双能X线吸收仪测量女儿腰椎1～4和股骨颈、大转子、粗隆间、总髋部及Ward’s三角的BMD值（g／cm^2）。PCR-RFLP方法分析所有研究对象VDR基因ApaⅠ多态性。用协方差分析（ANCOVA）和数量性状位点传递非平衡测验法（QTDT）对ApaⅠ多态性与BMD进行相关、连锁和相关模型下的连锁分析。结果 基因型频率分布符合Hardy-weinberg平衡定律。ANCOVA显示VDR基因ApaⅠ多态性与女性腰椎峰值BMD相关（P=0．047）；QTDT分析未发现VDR基因ApaⅠ多态性与腰椎及股骨近端各部位BMD值的相关和连锁。结论 本研究提示VDR基因ApaⅠ多态性与上海市女性峰值BMD值变异无关联和连锁。VDR基因ApaⅠ多态性不是上海市汉族女性峰值BMD值变异的数量性状位点。     

Vitamin D, parathyroid hormone levels and bone mineral density in community-dwelling older women: The Rancho Bernardo Study

Vitamin D (25(OH)D) increases the efficiency of intestinal calcium absorption. Low levels of serum calcium stimulate the secretion of parathyroid hormone (PTH), which maintains serum calcium levels at the expense of increased bone turnover, bone loss and increased risk of fractures. We studied the association between 25(OH)D and PTH levels, and their associations with bone mineral density (BMD), bone loss, and prevalence of hip fractures in 615 community-dwelling postmenopausal aged 50–97 years. Mean level of 25(OH)D and PTH were 102.0 nmol/l±35.0 nmol/l and 49.4 ng/l±23.2 nmol/l, respectively; 49% of women were current hormone therapy users. The overall prevalence of vitamin D insufficiency (25(OH)D<50 nmol/l) was 2%, and prevalence of high PTH levels (>65 ng/l) was 17.4%. In multiple linear regression analyses hip BMD was negatively and independently associated with PTH levels ( p =0.04), and positively and independently associated with 25(OH)D levels ( p =0.03). There were only 23 women (3.7%) who experienced a hip fracture. In age-adjusted analyses there were no significant differences of 25(OH)D and PTH levels by hip fracture status. Across the entire range of values, the overall correlation between 25(OH)D and PTH was moderate ( r =–0.20). However, after the threshold vitamin D level of 120 nmol/l, all PTH values were below 65 ng/l. Further studies are necessary to identify the optimal vitamin D levels necessary to prevent secondary hyperparathyroidism.     

老年男性维生素D受体基因多态性与骨密度关系的研究

目的研究维生素D受体(vitamin D receptor,VDR)基因多态性在老年男性中的分布, 并进一步研究其与骨密度的关系。方法采用聚合酶链反应-限制性片段长度多态性(PCR- RFLP)方法,分析145例老年男性的VDR基因型,同时用双能X线吸收法测定腰椎及髋部骨密度。结果 VDR基因型分别为BB,0．014;Bb,0．117;bb,0．869。骨质疏松组与非骨质疏松组之间VDR基因型分布频率的差异无显著性(P>0．05)。比较各基因型组的骨密度,bb组及 Bb组只有在股骨颈处显示出BMD均低于BB组,差异有显著性(P<0．05),其它部位,三个基因型组的BMD均差异无显著性(P>0．05)。结论老年男性VDR基因型分布频率与某些西方国家人群分布不同,其VDR基因型与骨密度无明显相关性。VDR基因可能不是我们所研究群体 BMD的主要遗传基因。     

Correlation of vitamin D,bone mineral density and parathyroid hormone levels in adults with low bone density

Background:

Bone mineral densiy (BMD) is known to be affected by serum 25-hydroxyvitamin D (25(OH) D) levels, intact parathyroid hormone (iPTH) levels. Indian data pertinent to above observation is scant. Our study aimed to investigate the relationships between serum 25-hydroxyvitamin D (25(OH) D) levels, intact parathyroid hormone (iPTH) levels and bone mineral density (BMD) in a cohort of Indian patients.

Materials and Methods:

Adults with or without fragility fractures with low BMD at the hip or lumbar spine were evaluated clinically along with laboratory investigations. T-scores of the hip and spine were derived from BMD-DEXA (dual-energy X-ray absorptiometry). Multivariate regression models were used to investigate the relationships between serum 25(OH) D, iPTH and BMD.

Results:

Total of 102 patients (male:female = 38:64) with a mean age of 62.5 ± 6.4 years were included in the study. Forty-four patients had osteopenia. Osteoporosis was present in 58 patients. The mean values for serum 25(OH) D and iPTH levels were 21.3 ± 0.5 ng/ml and 53.1 ± 22.3 pg/ml, respectively. In 84.3% of patients, serum 25(OH) D levels were below 30 ng/ml (Normal = 30-74 ng/ml), confirming vitamin D deficiency. There was no association between 25(OH) D levels and BMD at the hip or lumbar spine (P = 0.473 and 0.353, respectively). Both at the hip and lumbar spine; iPTH levels, male gender, body mass index (BMI) and age were found to be significant predictors of BMD. Patients with higher BMI had significantly lower BMD and T-score. At levels <30 ng/ml, 25(OH) D was negatively associated with iPTH (P = 0.041).

Conclusion:

Among our cohort of patients with low BMD, no direct relationship between serum 25(OH) D levels and BMD was observed. However, a negative correlation between iPTH and 25(OH) D at serum 25(OH) D concentrations <30 ng/ml. Serum iPTH levels showed a significant negative association with BMD at the hip and lumbar spine. Our findings underscore the critical role of parathyroid hormone in bone metabolism and health.     

The association between vitamin D receptor gene polymorphisms and bone mineral density at the spine,hip and whole-body in premenopausal women

The genetic influence on bone mineral density (BMD) is thought to be mediated in part by alleles at the vitamin D receptor (VDR) locus. In order to assess the effect of VDR on BMD in premenopausal women, we studied 470 healthy white subjects, aged 44–50 years, participating in the Women's Healthy Lifestyle Project. Each participant was genotyped for theBsmI polymorphism at the VDR gene locus. BMD at the lumbar spine, hip and whole-body, and the whole-body soft tissue composition, were measured cross-sectionally using a Hologic QDR 2000 densitometer. The presence of a polymorphic restriction site at the VDR gene locus was specified asb, whereas absence of this site wasB. The frequency distribution of the VDR genotype was:bb, 20.6%;Bb, 39.1%; andBB, 40.2%. Spinal BMD (mean±SD) was significantly lower in women with VDR genotypeBB (1.038±0.11 g/cm²) as compared with those with genotypebb (1.069±0.12 g/cm²,p<0.05). Trochanter BMD was 2.7% lower in those with genotypeBB versusbb (0.685±0.10 g/cm² vs 0.708±0.09 g/cm²). A similar trend was shown at each subregion of the hip, but not at the whole-body. In premenopausal women, allelic status at the VDR locus contributed to variations in spinal and trochanteric BMDs, but the absolute difference in BMDs was small, amounting to 0.26 and 0.23 standard deviations, respectively. It is concluded that in this population of healthy premenopausal women there was a significant association between polymorphisms at the VDR gene locus and both spinal and trochanteric BMDs, yet no association was demonstrated for the whole-body BMD.     

Association of vitamin D and estrogen receptor gene polymorphism with the effects of longterm hormone replacement therapy on bone mineral density

We longitudinally studied whether vitamin D receptor (VDR) and estrogen receptor (ER) gene polymorphisms in Japanese women influenced the effect of longterm hormone replacement therapy (HRT) on bone mineral density (BMD) in the lumbar spine. The 81 subjects were aged 40 to 64 years (mean ± SEM, 49.5 ± 0.6 years), and had received sequential or continuous HRT regimens, including 0.625mg of conjugated equine estrogen and 2.5 to 5mg of medroxy-progesterone acetate, for at least 3 years. Genomic DNA was extracted from blood cells, and analyzed for restriction fragment length polymorphism, using the restriction endonucleases Taq I, Apa I, and Fok I for VDR, and Pvu II and Xba I for ER. At 1 year, subjects with a Taq I genotype of TT (i.e., site absent) showed a significantly greater increase in BMD with treatment (BMD) than subjects with the Tt genotype (2.6 ± 0.5% vs –0.8 ± 1.4%; P = 0.016). A small difference between genotypes remained at 2 years (3.8 ± 0.6% vs 0.8 ± 1.6%; P = 0.069), but no significant difference between genotypes was seen at 3 years. In multiple regression analyses, BMD at 1 year was significantly affected by VDR-Taq I, Apa I, and ER-Pvu II genotypes and by age at treatment initiation, although at 3 years or more, BMD was significantly affected only by age. These results indicate that Taq I VDR gene polymorphism predicted the effect on lumbar BMD for the first year of HRT in Japanese women, and that the differences in BMD versus the polymorphism disappeared if the treatment was continued for over 2 years.     

老年男性甲状旁腺激素与骨密度的关系

本文的目的在于探讨在健康老年人中，甲状旁腺素（ＰＴＨ），钙（Ｃａ）、磷（Ｐ）、镁（Ｍｇ）、碱性磷酸酶（ＡＫＰ）、肌酐（Ｃｒ）与骨密度（ＢＭＤ）之间的关系。选择７０名健康老人，抽血查Ｃ－ＰＴＨ、Ｃａ、Ｐ、Ｍｇ、ＡＫＰ和Ｃｒ的水平。并在左侧桡骨远端１／３处，用单能光子骨密度测定仪测定ＢＭＤ。以正常参考值为标准（０．６２９７～０．７６９５ｇ／ｃｍ２），将对象分为ＢＭＤ降低组和ＢＭＤ正常组。结果显示：（１）在ＢＭＤ正常组（ＢＭＤ值为０．７３±０．０７ｇ／ｃｍ２）中，ＰＴＨ的水平为１５５．３６±９３．４５（ｎｇ／Ｌ），在ＢＭＤ降低组（ＢＭＤ值为０．５７±０．０４ｇ／ｃｍ２）中，ＰＴＨ的水平为２１４．１１±９１．９３（ｎｇ／Ｌ）。二组间差异有统计学意义。（２）在ＢＭＤ正常组中，血清钙的水平为２．１２±０．２２（ｍｍｏｌ／Ｌ），在ＢＭＤ降低组中，血清钙的水平为２．２３±０．１９（ｍｍｏｌ／Ｌ）。两组相比，差别有统计学意义（Ｐ＜０．０５）。实验结果提示：在老年男性与年龄有关的骨密度降低中，ＰＴＨ的分泌起到重要作用。     

褪黑素受体1B基因多态性与青少年骨密度的相关性

目的探讨褪黑素受体1B基因(MTNR1B)多态性与骨密度之间的相关性。方法选取140名16~20岁之间的正常女性,采用双能X线骨密度吸收仪测量双侧近端股骨的骨密度。同时,采取外周静脉血,采用试剂盒提取DNA。根据人类单倍体图计划(HapMap)提供的汉族人数据,我们在MTNR1B基因上选取了6个标签SNP(tagSNPs)。通过PCR-RFLP的方法检测褪黑素受体1B基因上6个标签SNP的基因型。采用ANOVA的统计学方法比较不同基因型对应骨密度大小。结果MTNR1B基因6个多态性位点各基因型所对应的骨密度,没有明显差异(P>0.05)。结论褪黑素受体1B基因多态性与骨密度之间没有相关性。     

广西壮、汉族绝经后妇女维生素D受体基因型与骨密度的关系

目的 探讨维生素D受体基因(VDR)型在广西壮、汉族绝经后妇女中的分布及其与骨密度(BMD)的关系。方法 在广西居住20年以上、无血缘关系的健康绝经后妇女198名,其中三代均为壮族的116名,均为壮族的82名。记录他们的年龄、绝经年龄,测量他们的身高、体重。用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法测定受试者的VDR基因型;用双能X线吸收法测定髋部、腰椎和前臂的骨密度。结果 壮、汉两组妇女VDR基因型和VDR等位基因频率分布均无显著性差异(P>0.05);198名妇女BB、Bb、bb基因型检出率分别为6.57％、66.16％和27.27％;B、b等位基因分别为39.65％和60.35％。BB基因型组第二腰椎(L2)BMD较bb基因型组低10.03％(P=0.047),第四腰椎(L4)BMD分别较bb、Bb基因型组低9.63％(P=0.043)和12.44％(P=0.005)。BB基因型组骨质疏松发生率最高(46.15％),Bb基因型组次之(19.86％),bb基因型组最低(14.81％),差异有显著性(P=0.04)。结论 VDR基因型与广西壮、汉族绝经后妇女BMD有关联,BB基因型可能可作为预测广西壮、汉族绝经后妇女骨质疏松危险性的遗传学标志之一。     

2型糖尿病男性患者骨密度与性激素水平关系的研究

目的通过比较不同骨密度(bone mineral density,BMD)状态的2型糖尿病(type 2 diabetes mellitus,T2DM)男性患者性激素水平的差异,进一步探讨性激素与T2DM男性患者BMD的关系。方法收集2013年6月至2015年1月我院住院的男性T2DM患者84例,年龄在45~60岁。采用美国Norland双能X线骨密度检测仪对所有患者进行第1~4腰椎(L1~L4)、股骨颈(FN)及全髋(TH)部位BMD检测,根据BMD分为骨量正常组和骨量异常组(包括骨量减少和骨质疏松)。测定身高、体重、SBP、DBP等一般情况指标,并计算体重指数(body mass index,BMI);FBG、PBG、Hb Alc等糖代谢指标;TC、TG、LDL等脂代谢指标,T、E2、LH及FSH。结果 1与骨量正常组相比,骨量异常组病程更长,BMI更低,E2及T水平也显著降低。2相关分析显示,T与L1~L4、FN及TH三个部位BMD均呈正相关;E2仅与TH的BMD呈正相关;TC、LDL分别与FN的BMD呈负相关。3多元线性回归分析显示,在T2DM男性患者中,T及TC是影响FN的BMD的主要因素,而E2、LH、FSH未进入回归模型。结论 E2、T等性激素水平,TC、LDL等脂代谢指标与男性T2DM患者BMD相关,其中性激素中T是影响T2DM男性患者BMD的独立危险因素。