T-cell receptor V alpha and C alpha alleles associated with multiple and myasthenia gravis.

Polymorphic markers in genes encoding that alpha chain of the human T-cell receptor (TcR) have been detected by Southern blot analysis in Pss I digests. Polymorphic bands were observed at 6.3 and 2.0 kilobases (kb) with frequencies of 0.30 and 0.44, respectively, in the general population. Using the polymerase chain reaction (PCR) method, we amplified selected sequences derived from the full-length TcR alpha cDNA probe. These PCR products were used as specific probes to demonstrate that the 6.3-kb polymorphic fragment hybridizes to the variable (V)-region probe and the 2.0-kb fragment hybridizes to the constant (C)-region probe. Segregation of the polymorphic bands was analyzed in family studies. To look for associations between these markers and autoimmune diseases, we have studied the restriction fragment length polymorphism distribution of the Pss I markers in patients with multiple sclerosis, myasthenia gravis, and Graves disease. Significant differences in the frequency of the polymorphic V alpha and C alpha markers were identified between patients and healthy individuals.

通过对Pss I酶切产物进行Southern印迹分析，已在编码人T细胞受体（TcR）α链的基因中检测到多态性标记。在普通人群中，分别在6.3和2.0千碱基（kb）处观察到多态性条带，其频率分别为0.30和0.44。利用聚合酶链反应（PCR）方法，我们扩增了源自全长TcRα cDNA探针的选定序列。这些PCR产物被用作特异性探针，以证明6.3 kb的多态性片段与可变（V）区探针杂交，2.0 kb的片段与恒定（C）区探针杂交。在家族研究中分析了多态性条带的分离情况。为了寻找这些标记与自身免疫性疾病之间的关联，我们研究了多发性硬化症、重症肌无力和格雷夫斯病患者中Pss I标记的限制性片段长度多态性分布。在患者和健康个体之间，多态性Vα和Cα标记的频率存在显著差异。