HLA-Ⅲ类成份及其构成的补体型与重症肌无力相关性的研究

Study on the association of HLA-Ⅲ components and complotype with Myasthenia gravis

对42个无血缘关系的重症肌无力(MG)患者家庭及36个健康献血员家庭成员的EDTA血浆用琼脂糖高压电泳及免疫固定的方法对属于HLA-Ⅲ的Bf,C4A及C4B的遗传多态性及其构成的补体型进行了检测。通过家系分析及对比发现,MG的Bf基因频率与正常人无差异;C4A~*4的基因频率病人远大于正常人,而C4A~*2则较常人为小。在补体型方便,MG患者与正常人亦不相同:患者以S42的频率最高,常人则以S31最高。MG患者的S42、S31及S40之间存在着正向连锁不平衡,S32和S41之间存在着负向连锁不平衡。进一步分析显示,S42与MG密切相关,这主要是由于C4A~*4与MG强烈相关,而Bf~*S和C4A~*2又与C4A~*4连锁不平衡的结果。

Allotypes and complotypes of Bf, C4A and C4B in 42 families with myasthenia gravis (MG) were determined by means of high voltage agarose gel elect rophoresis of EDTA plasma and subsequent immunofixation, in an attempt to determine whether specific allotypes and/or complotypes were associated with this disease. From the family-data, 108 complotypes were obtained, which could be classified into 28 kinds of complotypes. We found that there are positive linkage disequilibra in S42, S31 and S40,and negative linkage disequilibra in S32 and S41. Compared of these results with those of normal controls, the frequency of S42 is significantly increased in MG(P 0.05).Furhter analysis showed that the MG associated S42 may result from that C4A4 is strongly associated with MG, while C4A4 is in linkage disequilibrium with Bf S and C4A2. Preliminary association mechanism between C4A4 and MG was analysed and discused.