散发性重症肌无力患者267例维生素D受体基因多态性

目的 探讨中国汉族人维生素D受体(VDR)基因Fok Ⅰ和Apa Ⅰ位点多态性与重症肌无力(MG)的关系.方法 采用聚合酶链反应-限制性内切酶片段多态性(PCR-RFLP)法检测VDR基因Fok Ⅰ和Apa Ⅰ位点的多态性,比较基因型和等位基因在健康对照组及各MG亚组中的分布,并观察其与MG严重程度和激素短期疗效的关系.结果 Fok Ⅰ和Apa Ⅰ位点的基因型和等位基因频率在MG组和对照组间以及MG各亚组间的分布差异无统计学意义.Fok Ⅰ位点的基因型和等位基因频率在激素短期疗效好和疗效差组间的分布差异亦无统计学意义;但Apa Ⅰ位点的A等位基因频率在两组间差异有统计学意义,疗效好者(55/186,29.6%)高于疗效差者(7/48,14.6%,OR=2.46,95%CI 1.04～10 43,x2=4.400,P=0.036);激素短期疗效好者中携带基因型AA及Aa的频率(48/93,51.6%)高于疗效差者(7/24,29.2%,OR=2.59,95% CI 0.98～14.60,x2=3.858,P=0.049).结论 在我国汉族人散发性MG患者的VDR基因中,未发现Fok Ⅰ和Apa Ⅰ变异位点显著增加MG的患病风险,但携带Apa Ⅰ位点的A等位基因的MG患者激素短期疗效可能较好.

Abstract：

Objective To explore the associations between vitamin D receptor ( VDR) Fok- Ⅰ and Apa- Ⅰ polymorphisms and myasthenia gravis (MG) in Chinese Han population.Methods Polymorphisms of VDR Fok- Ⅰ and Apa-Ⅰ were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.The frequencies of genotypes and hyplotypes were compared among 286 normal controls and 267 MG patients in different subgroups classified by gender,age of onset,presence of thymoma,and Osserman classification sat maximal severity in the follow-up.The association between the genotypes and maximal severity of MG and short-term glucocorticoid treatment were also investigated.Results There were no significant differences in frequencies of genotypes and hyplotypes of both Fok-Ⅰ and Apa-Ⅰ between MG group and control group,and among subgroups of MG.The Fok- Ⅰ showed no statistical difference between the patients with better and less improvement after short-term treatment of glucocorticoid.The frequency of Apa-Ⅰ alleles in the patients with better improvement (55/186,29.6% ) significantly differed from the less improved group ( 7/48,14.6%,OR = 2.46,95% CI 1.04-10.43,x2 = 4.400,P = 0.036).The patients with the genotype A A/Aa were more likely to improve better after the treatment(48/93,51.6%) than in the worse group(7/24,29.2%,OR =2.59,95% CI 0.98-14.60,x2 =3.858,P= 0.049).Conclusions Alleles and genotypes of VDR-Fok- Ⅰ and Apa-Ⅰ were not found to be related with MG onset and severity.MG patients with VDR-Apa-A allele may have better improvement short-term treatment of glucocorticoid.