摘要目的 分析脊髓小脑性共济失调3型(SCA3)患者的基因型和表型特点,并探讨基因型-表型相关性. 方法 收集上海交通大学医学院附属瑞金医院自2005年7月至2015年12月收治的来自160个家庭的187例基因诊断明确的SCA3患者临床资料,以及ATXN3基因型检测结果.对患者临床表型及A TXN3基因CAG病理拷贝数进行统计分析. 结果 187例SCA3患者中男性100例,女性87例;平均发病年龄(35.43±.11.17)岁.CAG病理拷贝数范围为65～86次,平均(74.11±3.56)次.CAG病理拷贝数与发病年龄呈负相关(r=-0.815,P=0.000).CAG病理拷贝数较低者(≤74次)和较高者(＞74次)腱反射减退的发生率分别为28.9％和6.0％,肌强直的发生率分别为27.8％和49.4％,差异均有统计学意义(P＜0.05). 结论 SCA3是一种具有高度临床表现异质性和遗传学异质性的神经系统退行性疾病.ATXN3基因CAG病理拷贝数与发病年龄以及腱反射减退、肌强直的发生存在明显关联.

abstractsObjective To discuss the genotype and phenotype features of 187 patients with spinocerebellar ataxia type 3 (SCA3) and analyze their genotype-phenotype relationship.Methods A total of 187 patients genetically diagnosed as having SCA3 from 160 families were enrolled from our hospital from 2005 to 2015.Detailed medical histories were collected.SPSS 22.0 was conducted to statistically analyze the genotypes and pathogenic CAG expansions of A TXN3 gene in the patients.Results One hundred males and 87 females suffered SCA3.Mean age at onset was 35.43±11.17 years.The ranges of pathogenic CAG expansion were 65-86 repeats,with mean pathogenic CAG expansion of 74.11±3.56 repeats.A negative correlation was found between number of CAG repeats and age of onset (r=-0.815,P=0.000).Frequencies of the patients with tendon hyporeflexia were 28.9％ and 6.0％,respectively,in the smaller pathogenic CAG expansion group (≤74) and larger pathogenic CAG expansion group (＞74),with significant difference (P＜0.05).Frequencies of patients with rigidity were 27.8％ and 49.4％,respectively,in the smaller pathogenic CAG expansion group and larger pathogenic CAG expansion group,with significant difference (P＜0.05).Conclusions SCA3 is neurodegenerative disorder with high clinical and genetical heterogeneity.There are distinct correlations between number of pathogenic CAG expansion and age of onset,frequency ofhyporeflexia and rigidity.