【摘要】 目的检测我国南方地区Huntington舞蹈病(Huntington disease,HD)4个家系患者IT15基因突变特点,为该病的基因诊断和遗传咨询提供科学依据。方法收集4个HD家系成员临床资料,采集静脉血提取DNA后应用PCR方法检测IT15基因CAG三核苷酸重复序列,分析CAG拷贝数分布及其与临床特点和发病年龄的关系。结果4个家系中共有13例患者,平均发病年龄41.23±10.28岁,首发症状1例为精神障碍,12例为运动障碍。IT15基因检测结果显示,所有患者异常等位基因CAG平均重复次数45.62±2.90次(41~51次),检测出临床症状前亲属1例,携带1条异常等位基因(CAG重复41次);正常等位基因CAG重复次数均在22次以下(17~20次)。不同性别、遗传方式间CAG重复次数无统计学差异(P>0.05)。异常等位基因CAG重复次数与发病年龄呈负相关(P=0.03)。结论IT15基因动态突变是家族性HD发病的遗传学基础,IT15基因检测有助于确诊HD和临床症状前患者。更多还原

【Abstract】 Objective To investigate the genetic mutation in families of Huntington’s disease(HD) from South China and to provide the theoretical basis for genetic diagnosis and consultation for the disease.Methods PCR amplifi cation was performed to test the CAG repeats of T15 gene in 73 individuals from 4 families of HD.Results Thirteen pa tients were clinically diagnosed as having HD in the 4 families. The mean onset age of patients was 41.23±10.28 years.Initial symptoms were movement disorder in twelve patients and psychiatric impairment in one patient. All affected indi viduals had an abnormal allele ranging from 41 to 51 CAG repeats(the mean repeat size was 45.62± 2.90 and a normal allele(17~20 CAG repeats). One presymptomatic individual had an abnormal allele(41 CAG repeats) and a normal one(17 CAG repeats). There were no significant difference in CAG repeat regarding gender and inherited pattern(P>0.05).However, the CAG repeat size was negatively correlated with age of onset(P=0.03).Conclusions The genetic bases of fa milial HD from South China are associated with the dynamic mutations of IT15 gene.更多还原