β2肾上腺素能受体基因多态在重症肌无力发病机制中的作用

目的 探讨β2肾上腺素能受体(β2-AR)基因16位、27位密码子遗传多态在重症肌无力(myasthenia gravis,MG)发病机制中的作用.方法 应用聚合酶链反应-限制性片段长度多态(PCR-RFLP)方法和PCR产物直接测序检测88例MG患者组和91名性别、年龄相匹配的健康对照(HC)的β2-AR基因16位点和27位点多态分布特征.结果 β2-AR基因16位点Arg/Arg、Arg/Gly和Gly/Gly基因型频率在MG组依次为44.4%、38.6%和17.0%,HC组依次为29.7%、58.2%和12.1%,两组间差异有统计学意义(X~2=6.898,P=0.032).Arg和Gly的等位基因频率在MG组分别为63.6%和36.4%,HC组为58.8%和41.2%,两组间差异无统计学意义.β2-AR基因27位点Gln/Gln、Gln/Glu和Glu/Glu基因型频率在MG组依次为77.3%、20.4%和2.3%,HC组依次为78.0%、18.7%和3.3%,两组间差异无统计学意义.Gln和Glu等位基因频率在MG组为87.5%和12.5%,HC组为87.4%和12.6%,两组间差异无统计学意义.两组的基因型多态分布均符合Hardy-Weinberg定律.结论 β2-AR 16位点基因多态可能是MG发病的独立危险凶素,27位点基因多态与MG发病无明确相关性.

Role of β2-adrenergic receptor polymorphisms in pathogenesis of myasthenia gravis

Objective To explore the correlation of two β2-adrenergic receptor (β2-AR)polymorphisms (Arg16Gly,Gln27Glu) with the pathogenesis of myasthenia gravis (MG).Methods The genotypes of β2-AR in 88 MG patients and 91 age and gender-matched healthy controls (HC) were determined by polymerese chain reaction-restriction fragraent length polymorphism (PCR-RFLP) analysis.Results The frequencies of three genotypes (Arg/Arg,Arg/Gly and Gly/Gly) in position 16 were 44.4%,38.6%,17.0% in MG group and 29.7%,58.2%,12.1% in HC group respectively.The difference in distribution of the genotypes between MG group and HC group was statistically significant (X~2=6.898,P=0.032).The frequencies of Arg and Gly allele were 63.6% and 36.4% in MG group,and 58.8% and 41.2% in HC group.The difference in distribution of the alleles between MG group and HC group was statistically insignificant.The frequencies of 3 genotypes (Gln/Gln,Gln/Glu and Glu/Glu) in position 27 were 77.3%,20.4% and 2.3% in MG group and 78.0%,18.7%,3.3% in HC group respectively.The frequencies of Gin and Glu allele were 87.5%,12.5% in MG group,and 87.4%,12.6% in HC group.There was no significant difference in distribution of genotypes or alleles between MG group and HC group.Conclusion β2-AR gene polymorphism in position 16 may independently increase the risk of onset of MG,and there is no correlation between the polymorphism in position 27 of β2-AR and the onset of MG.