目的 通过研究维生素D受体(vitamin D receptor,VDR)基因多态性与湖南地区儿童支气管哮喘的相关性,探讨儿童支气管哮喘发病的遗传易感因素。方法 应用聚合酶链反应 -限制性长度多态性的方法 检测71例支气管哮喘及71 例正常对照儿童的维生素D 受体ApaI、BsmⅠ基因多态性,比较两组的基因型及其等位基因的分布频率;采用酶联免疫方法 检测维生素D(VD)及白介素-4(IL-4)、白介素-12(IL-12)。结果 两组儿童ApaI基因多态性及其等位基因的分布频率差异均有统计学意义(P＜0.05),而 BsmⅠ基因分布频率差异无统计学意义(P＞0.05);哮喘儿童血清25(OH)D₃及IL-12平均水平显著低于正常对照组儿童,而IL-4平均水平显著高于正常对照组儿童,差异有统计学意义(P＜0.05)。结论 VDR-ApaI基因可能是儿童支气管哮喘的遗传易感基因,而与VDR-BsmI基因多态性无关;VD作为一种免疫调节剂与支气管哮喘的发生、发展关系密切,增加VD的摄入量在一定程度上可能降低哮喘发病率。

Objective To investigate the genetic predisposing factor of childhood bronchial asthma through a study of the relation of the children's polymorphisms of vitamin D receptor (VDR) genes and bronchial asthma in Hunan province.Methods There were 71 children of the bronchial asthma group and the same number of normal children of the control group.Their polymorphisms of VDR genes including ApaI and BsmI were detected and compared by the use of polymerase chain reaction - restriction fragments length polymorphism(RFLP).The level of vitamin D and interleukin 4 and 12 were detected through enzyme-linked immunoassay. Results There were both statistical differences in the polymorphism of ApaI gene and the frequency of distribution of its allele between two groups (P<0.05),while the difference of them of BsmI gene was no significance (P>0.05);Comparing with the control group,the average levels of serum 25(OH)D₃ and interleukin 12 were significant lower while interleukin 4 was significant higher (P<0.05).Conclusion s Childhood bronchial asthma is correlated with the polymorphisms of VDR-ApaI,but it has no relation to the VDR-BsmI.The VDR-ApaI may be a genetic susceptibility gene.As an immune regulator,vitamin D is closely associated with the occurrence and development of childhood bronchial asthma,increasing the intake of vitamin D perhaps could reduce the incidence of asthma in a certain extent.