家族性重症肌无力临床特点及其与人类白细胞抗原DQA1基因多态性的相关性研究

目的探讨家族性重症肌无力(MG)的临床特点及其与人类白细胞抗原(HLA)DQA1基因多态性的相关性。方法对15例家族性、36例散发性MG患者的临床特点进行研究,并运用聚合酶链反应序列特异性引物(PCR SSP)对HLA DQA1基因多态性进行分型。结果与散发性MG相比,家族性MG患者发病年龄较早(两者分别为18 7、34 4岁,P=0 006),病情较轻,预后较好;与散发MG组及健康对照组比较,家族性MG患者的DQA1 0301基因频率增高(三者分别为40 0%、19 4%和20 2% ),差异有统计学意义(P<0 05),这种差异在眼肌型的患者中同样存在,但未发现患者性别与DQA1相关。结论家族性MG有其独特的临床特点,DQA1 0301是家族性尤其是眼肌型MG的易患基因,提示家族性MG与散发MG可能有着不同的免疫遗传机制。

Clinical features and HLA-DQA1 polymorphism in familial myasthenia gravis

Objective To analyze the association between HLA-DQA1 gene polymorphism and familial myasthenia gravis and the features of these patients.Methods The clinical features of 15 familial myasthenia gravis patients and 36 sporadic myasthenia gravis patients were analyzed. All the patients and 47 healthy controls were investigated for HLA-DQA1 genotyping by polymerase chain reaction-sequence specific primers (PCR-SSP).Results Familial patients had an earlier onset age (18.7vs34.4, P=0.006), less severity and good prognosis. Compared with sporadic myasthenia gravis patients and healthy controls, the frequency of DQA1*0301 allele was higher in familial myasthenia gravis patients (40% vs 19.4% vs 20.2%, P<0.05). The difference had statistical significance. In the ocular form this difference existed, too. There was no association between sex of the familial patients and DQA1 polymorphism.Conclusions Familial myasthenia gravis has different clinical features. HLA-DQA1*0301 allele should be positively related to the genetic susceptibility of familial myasthenia gravis patients especially to the ocular form, and familial myasthenia gravis is maybe different from sporadic patients in genetic immune mechanism.