一个回族家系亨廷顿舞蹈病的临床特征与基因突变分析

Clinical characteristics and genetic mutation analysis in a Hui family with Huntington disease

目的分析1个回族家系亨廷顿舞蹈病的临床表现与基因突变特点。方法应用降落聚合酶链反应（touchdownPCR）、分子克隆及基因测序等技术对1个临床诊断为亨廷顿舞蹈病的回族家系成员进行IT15基因检测。结果先证者首发症状为双下肢疼痛，逐渐发展为舞蹈样不自主运动、情绪异常、记忆力、智力减弱等，其染色体4p16．3的IT15基因异常片段cAG重复次数为46次；其子为症状前患者CAG重复次数为44次。结论该家系存在母系传递过程中IT15基因上CAG重复次数减少的现象，并发现1例CAA插入。

Objective To perform clinical analysis and gene diagnosis of Huntington disease （HD） in a Hui pedigree from Xinjiang. Methods The IT15 gene mutation of the Hui family was analyzed by touchdown PCR, molecular cloning and gene sequencing. Results The proband carried 46 CAG repeats. Pain in bilateral lower limb was the first symptom, followed by symptoms such as dance-like involuntary movements, mood disorders, impaired memory and intelligence. Asymptomatic son of the proband carried 44 CAG repeats. Conclusion This family showed reduced CAG trinucleotide repeats of IT15 gene during maternal transmission. A CAA variation is also detected within the CAG repeat region.