脊髓小脑性共济失调症状前诊断初探

Presymptomatic diagnosis of spinocerebellar ataxia

目的探讨脊髓小脑性共济失调(SCA)症状前患者的遗传学特征及症状前诊断的作用。方法对临床诊断为SCA的患者进行基因诊断,采用PCR法对家系"健康"成员的三核苷酸重复序列进行基因检测,并进行随访。结果通过基因检测,本组共检出7个SCA3家系,共25例患者和5例症状前患者;1个SCA1家系,其中患者2例和症状前患者1例;并对2名有类似轻微SCA临床表现的SCA3家系成员排除了SCA3诊断。SCA1家系中2例患者的CAG重复数为52和54,SCA3家系中25例患者的CAG重复数为64～78次。随访半年,SCA患者及症状前患者均无不良事件发生。结论基因诊断可以作为SCA患者症状前诊断的依据。

Objective To investigate characteristics of molecular genetics for presymptomatic patients with SCA and the role of presymptomatic diagnosis.Methods Genetic testing was carried out for patients and the ＂healthy＂ individuals from the SCA families,then we followed up the patients and presymptomatic patients.Results We had detected 7 SCA3 families and 1 SCA1 family by genetic testing.There are 25 patients and 5 presymptomatic patients in the SCA3 families,2 patients and 1 presymptomatic patient in the SCA1 family.Two at-risk SCA subjects who had minor signs were excluded from the diagnosis of SCA3.The CAG repeats of 2 cases in SCA1 family were 52 and 54,and the CAG repeats of 25 cases in SCA3 families were 64 to 78.There were no adverse events occured in presymptomatic patients during the half-year follow-up.Conclusions Genetic testing could be used as presymptomatic diagnosis.