GJB1基因突变致腓骨肌萎缩症一家系

GJB1 gene mutation associated with Charcot-Marie-Tooth disease:a pedigree analysis

分析X-连锁腓骨肌萎缩症1型(X-linked Charcot-Marie-Tooth disease type 1,CMT1X)一家系的临床表现、电生理与突变基因特点。该家系为两代4人,共有2例CMT1X患者。先证者12岁起病,先证者母亲40岁起病,两者均表现为进行性肢体无力、萎缩,行走不稳。神经电生理检查均提示:四肢多发感觉运动神经损害(轴索损害为主并脱髓鞘);多发肌肉呈神经源性损害。突变基因分析,先证者存在缝隙连接蛋白B1(gap junction protein Bata-1,GJB1)基因c.283 G>T(p.V95L)半合子突变,先证者母亲存在GJB1基因c.283 G>T(p.V95L),杂合突变。CMT1X是第二常见的腓骨肌萎缩症(Charcot-Marie-Tooth disease,CMT)类型,由GJB1基因突变引起,临床表现为进行性发展的周围神经病可合并中枢神经系统损害,基因检测有助诊断。

To analyze the clinical manifestation,electrophysiologyand mutant genes of a family with X-linked Charcot-Marie-Tooth disease type 1(CMT1X).Two cases of CMT1X were found in a two-generation family of 4 members.The onset of the disease was at the age of 12 years in the proband and 40 years in the proband's mother,both presented with progressive limb weakness,atrophy,and unstable walking.Neurophysiological examination showed multiple sensorymotor nerve damage(predominantly axonal damage and demyelination)in the extremities and neurogenic damage in multiple muscles.Mutant gene analysis showed that there was a hemizygote mutation of gap junction protein Bata-1(GJB1)gene c.283 G>T(p.V95L)in the proband and a same heterozygous mutation of GJB1 gene c.283 G>T(p.V95L)in his mother.CMT1X is the second most common type of Charcot-Marie-Tooth disease(CMT)caused by the mutation of GJB1 gene,which is characterized by progressive peripheral neuropathy and possible central nervous system damage.Genetic test is helpful for its diagnosis.