浙江沿海一家系脊髓小脑性共济失调的基因突变检测与临床表现

摘要

Objective To study the clinical features and gene mutation analysis in Machado-Joseph disease of spinocerebellar ataxia type 3 in littoral of Zhejiang. Methods Clinical manifestation and brain MRI data 18 patients with SCA in family were analyged. The gene mutations of 18 patients and 10 family numbers without abnormal presentation,and 12 healthy persons of controls. Results The gene mutations of 18 patients is SCA3/ MJD,and 2 asymptomatic SCA3/MJD had been detected in SCA family. Normal alleles of SCA3/MJD have CAG repeats ranging from 14 to 27, patients from 67 to 82, asymptomatic and carrier SCA3/MJD from 28 to 45. The main features of 18 patients included gait ataxia, ambiguity in speech and action clumsiness. Brain MRI showed remarkable atrophy on cerebellum and brain stem. Conclusion CAG expansions were related to SCA3/MJD.The clinical manifestations are ataxia and dysarthria. The detection of repeated times CAG can provide an effective way for the genetic and asymptomatic diagnosis.%目的 探讨浙江沿海脊髓小脑性共济失调的基因突变检测与临床表现.方法 对该家系18例患者的临床表现、头颅MRI等辅助检查资料分析,并与10名家系中未发病成员及12名非血缘的健康人进行SCA31MJD基因CAG三核苷酸重复数目比较.结果 家系18例患者均为SCA3/MJD型,同时检测出家系中未发病对照组有2例为SCA31MJD型基因携带者.产物测序结果家系对照组与健康对照组CAG重复数为14～27次;SCA患者CAG重复数为67～82次;SCA3/MJD携带者CAG重复数为28～45次.在现存三代18例患者中,每代均有患者,男女均受累,起病年龄平均38岁,以行走不稳、动作笨拙和言语含糊为突出表现,MRI检测结果小脑、脑干明显萎缩.结论 在我国沿海存在SCA3/MJD家系遗传.临床均以共济失调和构音障碍为突出,CAG重复数目检测可为基因诊断和症状前诊断提供依据.