维生素D受体基因多态性与维生素D缺乏性佝偻病易感性的研究

目的 通过研究维生素D受体(VDR)基因多态性与维生素D缺乏性佝偻病易感性的相关性,探讨维生素D缺乏性佝偻病的遗传易感因素。方法 利用限制性内切酶FokI,应用聚合酶链反应-限制性片段长度多态性(PCR—RFLP)分析、基因测序等技术测定48例维生素D缺乏性佝偻病患儿(病例组)和92名正常儿童(对照组)的VDR基因多态性,比较两组VDR基因型和等位基因的分布频率,并计算基因型优势比(OR)。结果 在48例佝偻病患儿中FF、Ff和ff基因型分布频率分别为46％、33％和21％;而在92名正常儿童中FF、Ff和ff基因型分布频率分别为22％、52％和26％。两组VDR基因型的分布频率差异有显著性(x^2=8．912,P=0．012),病例组中FF基因型占明显优势(OR=3．046)。两组VDR基因等位基因的分布频率差异也有显著性(x^2=5．451,P=0．020),病例组中F等位基因分布频率高于对照组。结论 VDR基因多态性与维生素D缺乏性佝偻病有相关性,提示VDR基因多态性可能在决定个体维生素D缺乏性佝偻病遗传易感性方面有重要作用。     

佝偻病维生素D受体基因多态性与25-羟维生素D3相关性

目的：研究1~3岁佝偻病患儿中维生素D受体基因多态性FokⅠ位点与佝偻病相关性,初步探讨维生素D受体基因多态性FokⅠ位点在佝偻病发病中的作用。方法：病例组（佝偻病患儿）62例与对照组（正常健康儿童）60例,用ELISA方法检测血清25-羟维生素D3水平,比较两组之间血清25-羟维生素D3水平。用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）检测病例组和对照组维生素D受体基因多态性FokⅠ位点,比较两组之间基因型和等位基因分布频率。结果病例组血清25-羟维生素D3水平较对照组明显降低,差异有统计学意义（9.1±4.1 ng/mL vs 16.1±6.9 ng/mL;P＜0.05）。维生素D受体基因多态性FokⅠ位点病例组FF基因型明显高于对照组（53% vs 25%）,基因型分布频率差异有统计学意义（χ2=10.221,P＜0.05）,病例组F等位基因频率明显高于对照组（73% vs 57%）,等位基因分布频率差异有统计学意义（χ2=7.511,P＜0.05）。结论维生素D受体基因多态性FokⅠ位点与佝偻病有相关性,提示其在佝偻病遗传易感性方面起重要作用。［中国当代儿科杂志,2010,12（7）：544-546］     

维生素D缺乏性佝偻病遗传易感性的研究

目的：遗传因素是否参与维生素D缺乏性佝偻病目前尚未明了。拟通过研究维生素D受体基因多态性与维生素D缺乏性佝偻病易感性的相关性,探讨维生素D缺乏性佝偻病的遗传易感性。方法：应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)分析技术检测159例维生素D缺乏性佝偻病儿童和78例正常儿童(对照组)维生素D受体(VDR)基因FokI位点的多态性,比较两组之间VDR基因型和等位基因的频率。结果：维生素D缺乏性佝偻病患儿和对照组儿童的VDR基因FokI位点基因型分布频率分别为:FF(37%),Ff(51%),ff(12%)和FF(18%),Ff(55%),ff(27%),两组之间的差异有显著性(χ20.01(2)=9.210,χ2=13.3880,P<0.01);佝偻病患儿和对照组儿童的VDR基因FokI位点等位基因分布频率分别为:F(63%),f(37%)和F(46%),f(54%),两组之间的差异有显著性(χ2=6.18,P<0.05)。佝偻病患儿F等位基因分布频率明显高于对照组人群(63%vs46%)两组之间的差异有显著性;而佝偻病患儿f等位基因频率显著低于对照组(37%vs 54%)。结论：VDR基因FokI酶切位点的多态性可能与维生素D缺乏性佝偻病的遗传易感性有关。     

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目的研究维生素D受体(VDR)基因BsmI多态性分布,以及与维生素D缺乏性佝偻病的关系,探讨其遗传易感性。方法对象为41例维生素D缺乏性佝偻病患儿和68例健康对照组儿童,均为山西籍汉族儿童,应用聚合酶链反应限制性片段长度多态性分析(PCRRFLP)等技术测定VDR基因BsmI多态性,比较两组基因型和等位基因的分布频率,并用HardyWeinberg遗传平衡检验方法进行基因分布遗传平衡吻合度检验。结果佝偻病患儿组Bb、bb基因型分布频率分别为14.6%和85.4%,健康对照组儿童Bb、bb基因型分布频率分别为19.1%、80.9%。病例组等位基因B、b分布频率分别为7.35%、92.7%,对照组等位基因B、b分布频率分别为9.6%、90.4%,佝偻病组和正常对照组VDR基因型Bb、bb分布频率和等位基因分布频率间没有显著性差异。BsmI多态性分布极不平衡,bb型最多占80.9%,b位点占90.4%,是优势基因。结论VDR基因BsmI酶切位点多态性与维生素D缺乏性佝偻病发病无明显相关性。     

血清25-羟维生素D在佝偻病诊断中的应用价值

目的：探讨血清25 羟维生素D［25（OH）D］在维生素D缺乏性佝偻病早期诊断中的意义。方法：检测对照组（73例）、可疑组（45例）和佝偻病组（65例）的血清25（OH）D、钙、磷、碱性磷酸酶浓度,并通过ROC曲线对血清25（OH）D的诊断价值进行评价。结果：对照组、可疑组和佝偻病组的血清25（OH）D水平分别为112±37、83±30和72±31 nmol/L,后两者均显著低于对照组（F=26.174,P0.05）。可疑组和佝偻病组的维生素D缺乏率均显著高于对照组（χ2=33.346, P0.05）。结论：血清25(OH)D水平在可疑及确诊佝偻病的患儿中显著降低,可以反映维生素D的营养状况,适用于佝偻病的早期筛查。     

维生素D受体基因BsmI多态性与儿童佝偻病的关系研究

目的研究维生素D受体(VDR)基因BsmI多态性分布,以及与维生素D缺乏性佝偻病的关系,探讨其遗传易感性。方法对象为41例维生素D缺乏性佝偻病患儿和68例健康对照组儿童,均为山西籍汉族儿童,应用聚合酶链反应 限制性片段长度多态性分析(PCR RFLP)等技术测定VDR基因BsmI多态性,比较两组基因型和等位基因的分布频率,并用Hardy Weinberg遗传平衡检验方法进行基因分布遗传平衡吻合度检验。结果佝偻病患儿组Bb、bb基因型分布频率分别为14.6%和85.4%,健康对照组儿童Bb、bb基因型分布频率分别为19.1%、80.9%。病例组等位基因B、b分布频率分别为7.35%、92.7%,对照组等位基因B、b分布频率分别为9.6%、90.4%,佝偻病组和正常对照组VDR基因型Bb、bb分布频率和等位基因分布频率间没有显著性差异。BsmI多态性分布极不平衡,bb型最多占80.9%,b位点占90.4%,是优势基因。结论VDR基因BsmI酶切位点多态性与维生素D缺乏性佝偻病发病无明显相关性。     

维生素D受体基因多态性与维生素D缺乏性佝偻病遗传关联性Meta分析

目的:评价维生素D受体（VDR）基因多态性与维生素D缺乏性佝偻病(佝偻病)的遗传关联性。方法:制定原始文献的纳入标准及检索策略,检索PubMed、Springer、Science Direct、Web of Science、中国期刊全文数据库、维普中文科技期刊数据库和万方数据库,收集VDR基因FokⅠ、ApaⅠ、BsmⅠ和TaqⅠ位点多态性与佝偻病相关性的病例对照研究,以佝偻病患儿为病例组。依据NHI NHGRI研究工作组2007年制定的遗传关联性研究报告规范为基础,并依据相关文献选取其中的14条标准用于评价文献偏倚。以基因型频率为指标,提取数据后先确定最佳遗传模型,采用Stata 11.0软件进行Meta分析,计算合并的OR值及其95％CI。结果:19篇病例对照研究进入Meta分析。①FokⅠ位点采用共显性模型（FF基因型 vs ff基因型;FF基因型 vs Ff基因型）分析,病例组704例,对照组596例。Meta分析结果显示,亚洲人群FF基因型较ff基因型（OR=4.59,95%CI：2.98~7.07）和Ff基因型(OR=2.58,95%CI：1.79~3.73)患佝偻病的风险显著增加;高加索人群FokⅠ位点与佝偻病无显著关联性（FF基因型 vs ff基因型,OR=2.50,95%CI：0.76~8.19;FF基因型 vs Ff基因型,OR=1.18,95%CI：0.66~2.10）;非洲人群FF基因型较ff基因型患佝偻病的风险显著增加（OR=5.81,95%CI：1.21~27.98）。②ApaⅠ位点采用显性模型（AA+Aa基因型 vs aa基因型）分析,病例组338例,对照组459例。亚洲人群和非洲人群ApaⅠ位点与佝偻病均无显著关联性,OR分别为1.04（95%CI：0.72~1.49）和0.98（95%CI：0.57~1.71）;高加索人群AA+Aa基因型患佝偻病的风险增高（OR=5.50,95%CI：1.22~24.75）。③BsmⅠ位点采用显性模型（bb基因型 vs Bb+BB基因型）分析,病例组822例,对照组736例。亚洲人群BsmⅠ位点bb基因型较Bb+BB基因型患佝偻病的风险降低(OR=0.46,95%CI：0.23~0.92),非洲人群BsmⅠ位点与佝偻病无显著关联性（OR=1.65,95%CI：0.95~2.88）。④TaqⅠ位点采用隐性模型（TT基因型 vs Tt+tt基因型）分析, 病例组519例,对照组513例。亚洲人群（OR=1.22,95%CI：0.82~1.82）、高加索人群（OR=0.91,95%CI：0.35~2.35）和非洲人群（OR=1.18,95%CI：0.68~2.05）TaqⅠ位点与佝偻病无显著关联性。结论:现有证据表明,亚洲人群FokⅠ位点FF基因型为患佝偻病的危险因素,而BsmⅠ位点bb基因型为佝偻病轻微的保护因素,尚不能认为ApaⅠ和TaqⅠ位点与佝偻病有关联性;由于高加索人群和非洲人群研究较少,VDR基因多态性与佝偻病的关联性尚不明确。     

维生素D受体基因Fok Ⅰ、Taq Ⅰ多态性与女性婴幼儿佝偻病的相关性

目的 研究维牛素D受体(VDR)基因FokⅠ、TaqⅠ多态性分布及其与女性婴幼儿维生素D缺乏性佝偻病的关系,探讨其临床意义.方法 选择男性婴幼儿58例为佝偻病男童组,女性婴幼儿佝偻病60例为佝偻病女童组;健康男、女性婴幼儿62、58例分别为健康对照男童组及女章组;应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)分析等技术测定各组VDR基因Fok Ⅰ、Taq Ⅰ多态性,分别比较4组VDR基因Fok Ⅰ、Taq Ⅰ多态性分布频率.采用SPSS 13.0软件进行统计学分析.结果 佝偻病女童组与各对照组间比较,VDR的Taq Ⅰ基因型和等位基因分布频率均无显著性差异(Pa＞0.05).Fok Ⅰ基因型和等位基因分布频率在佝偻病女童组与健康对照女童组和健康对照男章组比较均有显著性差异(P=0,0,0.001,0.002);佝偻病女童组与佝偻病男童组比较无显著性差异(P＞0.05).结论 VDR基因部分位点多态性可能与女性婴幼儿佝偻病显著相关;VDR基因多态性在婴幼儿佝偻病中无性别差异.     

维生素D受体基因ApaI位点多态性与维生素D缺乏性佝偻病的研究

目的研究山西汉族儿童维生素D受体(VDR)基因ApaI位点多态性与维生素D缺乏性佝偻病的关系,探讨个体遗传因素在佝偻病发病中的意义,为临床防治探索一条新途径。方法以血清25(OH)D3水平、骨源性碱性磷酸酶(BALP)以及临床症状和体征作为分组指标,确定佝偻病组(40例)、对照组(68例)作为研究对象。应用酶联免疫和放射免疫方法,采用聚合酶链反应和限制性片段长度多态性技术(PCRRFLP)检测VDR基因ApaI位点多态性,HardyWeinberg遗传平衡检验方法进行基因分布遗传平衡吻合度检验。结果佝偻病组AA、Aa、aa基因型分布频率分别为5.0%、52.5%和42.5%。对照组AA、Aa、aa基因型分布频率分别为4.4%、55.9%、39.7%。佝偻病组等位基因A、a分布频率分别为31.3%、68.7%,对照组等位基因A、a分布频率分别为32.3%、67.7%。VDR基因型分布频率、等位基因分布频率两组间差异无统计学意义(χ2=0.089,P>0.05;χ2=0.028,P>0.05)。两组间血清25(OH)D3水平差异有统计学意义(t=-8.919,P<0.01)。结论(1)本组汉族儿童VDR基因ApaI位点多态性分布相对较均衡,a等位基因频率为67.7%,是优势基因。(2)本组人群VDR基因多态性分布与高加索人种相比明显不同,存在种族差异。(3)提示VDR基因ApaI位点多态性在个体是否发生维生素D缺乏性佝偻病方面可能没有意义。     

维生素D受体基因多态性与新疆南部地区维吾尔族儿童尿路结石相关性研究

目的：探讨维生素D受体（VDR）基因多态性与新疆南部地区维吾尔族儿童尿路结石相关性,阐明分子遗传学规律。方法：维吾尔族尿路结石患儿（病例组）74例和维吾尔族正常儿童（对照组）103例纳入此研究,应用聚合酶链反应-限制性片段长度多态性分析研究VDR基因FokI和ApaI位点多态性与新疆南部地区维吾尔族儿童尿路结石相关性。结果：VDR基因FokI位点FF、Ff、ff 3种基因型在病例组及对照组之间分布差异有统计学意义（χ2=7.818, P＜0.05）,基因型Ff在病例组占58%,明显高于对照组,差异有统计学意义（P＜0.05）。VDR基因ApaI位点AA、Aa、aa 3种基因型在病例组和对照组的分布差异无统计学差意义（P>0.05）。结论：VDR基因FokI位点多态性将来可作为维吾尔族儿童泌尿系结石的候选基因。     

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目的 探讨维生素D受体基因多态性与维生素D缺乏性佝偻病(佝偻病)遗传易感性的关系.方法 应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)分析技术检测2003年10月至2004年10月159例佝偻病患儿和78名健康儿童(对照组)VDR基因Bsm Ⅰ位点的多态性,比较两组之间VDR基因型和基因分布.结果 佝偻病患儿和对照组儿童的VDR基因Bsm Ⅰ位点基因型分布分别为:BB(0%),Bb(15.7%),bb(84.3%)和BB(0%),Bb(11.5%),bb(88.5%),两组间差异无统计学意义(P>0.05);佝偻病患儿和对照组儿童的VDR基因BsmⅠ位点等位基因分布分别为:B(7.9%),b(92.1%)和B(5.8%),b(94.2%),两组间差异无统计学意义(P>0.05).结论 VDR基因Bsm Ⅰ酶切住点的多态性与维生素D缺乏性佝偻病的遗传易感性相关关系尚须大样本进一步确定.     

Vitamin D receptor polymorphism in nutritional rickets

Although the pathophysiology of rickets and especially the central role of Vitamin D in this disease has been clarified since the 1920s, it is not completely understood why rickets is still prevalant in sunny countries. Furthermore, as we understand more about rickets, it appears that rickets is a heterogeneous disorder caused by vitamin D and/or Ca deficiency. Serum 25 and 1,25 OH vitamin D levels show a wide range of variation among children with rickets and the response to treatment is also variable. These observations suggest that individual susceptibility may play a role in the development of rickets. Polymorphisms in the Vitamin D receptor (VDR) gene were postulated to be associated with bone mineral density. VDR gene polymorphism could be influential in the development of rickets in some children as well. However, data in this regard are still scarce.     

Vitamin D receptor gene polymorphisms in Turkish children with vitamin D deficient rickets

Vitamin D deficient rickets is prevalent in Turkey and a considerable number of children are at risk of growth retardation, impaired bone formation and fracture. In order to check whether vitamin D receptor (VDR) gene polymorphism relates to the vitamin D deficient rickets, we analyzed VDR gene FokI, TaqI and ApaI polymorphisms in 24 Turkish vitamin D deficient rickets patients and 100 healthy controls. We found that "A" (ApaI) allele is more abundant in patients than controls (83 vs 57%, p = 0.002) but there were no significant differences for FokI (p = 0.693) and TaqI (p = 0.804) allele frequencies between patients and controls. We also showed that the frequency of Tt and Aa genotypes was significantly decreased in patients. Our results indicated that VDR gene polymorphisms might be an important factor for genetic susceptibility to vitamin D deficient rickets in the Turkish population.     

Case-control study of factors associated with nutritional rickets in Nigerian children

OBJECTIVE: Because the causes of nutritional rickets in tropical countries are poorly understood, we conducted a case-control study to determine factors associated with rickets in Nigerian children. STUDY DESIGN: We compared 123 Nigerian children who had rickets with matched control subjects. Dietary, demographic, anthropometric, and biochemical data were collected to assess factors related to calcium and vitamin D status, which might predispose children to rickets. RESULTS: Mean (+/- SD) daily dietary calcium intake was low in both children with rickets and control children (217 +/- 88 mg and 214 +/- 77 mg, respectively; P =.64). Children with rickets had a greater proportion of first-degree relatives with a history of rickets (14.6% vs 3.1%; P <.001), a shorter mean duration of breast-feeding (16.0 vs 17.3 months; P =.041), and a delayed age of walking (14 vs 12 months; P <.001). Among children with rickets, biochemical features suggestive of calcium deficiency included hypocalcemia, extremely low calcium excretion, and elevated 1, 25-dihydroxyvitamin D and parathyroid hormone values. Median 25-hydroxyvitamin D concentrations were 32 and 50 nmol/L (13 and 20 ng/mL) in children with rickets and control children, respectively (P <.0001). Only 46 subjects with rickets (37%) had 25-hydroxyvitamin D values <30 nmol/L (12 ng/mL). CONCLUSIONS: Vitamin D deficiency appears unlikely to be the primary etiologic factor of rickets in African children. Moreover, low dietary calcium intake alone does not account for rickets. Insufficient dietary calcium probably interacts with genetic, hormonal, and other nutritional factors to cause rickets in susceptible children.     

Early response to vitamin D2 in children with calcium deficiency rickets

OBJECTIVE: To assess the effect of vitamin D(2) administration on serum vitamin D metabolite concentrations in calcium deficiency rickets. STUDY DESIGN: We administered vitamin D(2), 50,000 IU orally to 16 Nigerian children 15 to 48 months of age with radiographically active rickets. We measured calcium and vitamin D metabolites at baseline and at 1, 3, 7, and 14 days. RESULTS: At baseline, ranges of serum 25-hydroxyvitamin D (25(OH)D) concentrations were 18 to 40 nmol/L (7-16 ng/mL), and 1,25-dihydroxyvitamin D (1,25-(OH)(2)D) concentrations were 290 to 790 pmol/L (120-330 pg/mL). After vitamin D administration, serum 25(OH)D and 1,25(OH)(2)D concentrations rapidly rose and peaked at 2.8 and 1.9 times the baseline values (P < .001), respectively, at 3 days. Positive correlations between 1,25(OH)(2)D and 25(OH)D were strongest at day 3 (r = 0.84, P < .001) and weakest at day 14 (r = 0.41, P = .11). The relationship of 1,25(OH)(2)D with 25(OH)D at baseline and the increase in 1,25(OH)(2)D in response to vitamin D were similar to those described in children with vitamin D deficiency. However, unlike the pattern in vitamin D deficiency, 1,25(OH)(2)D remained positively correlated with 25(OH)D after administration of vitamin D. CONCLUSION: Dietary calcium deficiency increases the demand for 25(OH)D above that required in vitamin D deficiency to optimize 1,25(OH)(2)D concentrations. Assessment of vitamin D sufficiency in persons or communities may need to be adjusted for habitual dietary calcium intake.     

Comparisons of oral calcium,high dose vitamin D and a combination of these in the treatment of nutritional rickets in children

Nutritional rickets remains a common child health problem in Turkey and many other developing countries. Although vitamin D deficiency is accepted as the basic problem underlying the disease, others postulate that a deficiency of dietary calcium, rather than vitamin D, is often responsible for the nutritional rickets in sunny countries. We conducted a placebo-controlled study to determine the best treatment regimen for nutritional rickets in children residing in lower socioeconomic regions of a sunny city, Istanbul. Forty-two infants (aged 6-30 months) with rickets were divided into three groups and included in the study. In a randomized fashion vitamin D (300 000 units, intramuscularly), calcium lactate (3 g daily) or a combination of vitamin D and calcium were given to the children. Alkaline phosphatase, calcium, albumin, ionized calcium and phosphorus levels were measured each week. X-ray examinations of the left wrist and left knee were undertaken at the beginning of the study and were repeated at the 2nd and 4th weeks and were scored in order to assess the response to treatment. Treatment produced an increase in serum calcium and a decrease in alkaline phosphatase concentration in all three groups, but the most important increase was reached in the vitamin D plus calcium group. We conclude that vitamin D deficiency appears to be the primary etiologic factor of rickets in our study group, but a better response to treatment with vitamin D or in combination with calcium was obtained than to treatment with calcium alone.