Abstract: Huntington disease（HD） is an autosomal dominant，inherited disease that causes the progressive breakdown of nerve cells in the brain.It is caused by expanded CAG repeats in the gene IT15.The clinical manifestations are involuntary movement and cognitive impairment.Neuroimaging shows caudate nucleus atrophy and lateral ventricle enlargement，partially accompanied by cortical atrophy.The gene test is a significant diagnosis for HD.For people with a positive family history and typical clinical manifestations，the diagnostic rate of this disease is higher; however，missed diagnosis and misdiagnosis often occur in patients with untypical symptom or at early stage of this disease.To investigate HD diagnosis and treatment，this article summarizes imaging and the CAG repeats sequence of the gene IT15 in a clinical suspected HD case and her two family members.Meanwhile，combined with the latest literature，we elucidate the advancement in the treatment of HD so as to improve the understanding of this rare disease.There is no effective treatment for HD at present，but gene therapy offers a new direction for treatment.

Key words: Chorea；Huntington disease；Repetitive sequences, nucleic acid；Genetic test；Case reports；Literature review

摘要： 亨廷顿舞蹈病（HD）是一种常染色体显性的神经退行性遗传病，由IT15基因外显子CAG三核苷酸重复突变所致，临床表现为不自主运动和认知功能障碍，影像学检查发现有尾状核萎缩，额角扩大，部分伴有皮质萎缩，基因检测是该病重要的诊断方式。对于有明确阳性家族史和典型临床表现，本病的诊断率较高；但对早期或不典型HD的诊断，临床常出现漏诊和误诊。为探讨HD的诊治，本文对1例临床疑似HD患者及2个家族成员进行影像学及IT15基因的CAG重复序列进行分析，并结合最新文献，阐述HD的发病机制及最新治疗进展，以提高对该病的认识。HD目前仍无有效治疗手段，但基因治疗为该病提供了新的方向。

关键词: 舞蹈症；亨廷顿舞蹈病；重复序列, 核酸；基因检测；病例报告；文献复习