摘要
The polymorphic CAG repeats in the IT15 gene in Chinese normal and Huntington’s dis-ease(HD)chromosomes were determined by using nested PCR and denaturing polyacry-lamide gel electrophoretic autoradiography as well as direct sequencing analysis.A total of40 normal individuals and 122 members of 13 unrelated HD families originating from Shang-hai,Jiangsu,Zhejiang,Anhui,Shandong,Guangdong and Henan,respectively,were in-volved in this study.The results showed that the(CAG)n repeat numbers in 270 normal al-leles ranged from 13 to 26 but most in 16;while in 54 HD alleles,the CAG repeats from 40to 94,with an unstable inheritance of expanded repeats in some families.There was no over-lap between the normal and affected alleles.Additionally,the presymptomatic diagnosis in103 family members at risk for HD disclosed that 35 individuals had HD alleles,which were-in accordance with the pedigree analysis and clinical investigation.All these results indicatedthat the dynamic mutation in IT15 gene was responsible for the genetic defect in the ChineseHD patients and that a correlation existed between the numbers of(CAG)n repeat and theonset age of the disease.All-of these provide valuable data for HD molecular diagnosis,ge-netic counselling and genetic health.
The polymorphic CAG repeats in the IT15 gene in Chinese normal and Huntington's dis- ease(HD)chromosomes were determined by using nested PCR and denaturing polyacry- lamide gel electrophoretic autoradiography as well as direct sequencing analysis.A total of 40 normal individuals and 122 members of 13 unrelated HD families originating from Shang- hai,Jiangsu,Zhejiang,Anhui,Shandong,Guangdong and Henan,respectively,were in- volved in this study.The results showed that the(CAG)n repeat numbers in 270 normal al- leles ranged from 13 to 26 but most in 16;while in 54 HD alleles,the CAG repeats from 40 to 94,with an unstable inheritance of expanded repeats in some families.There was no over- lap between the normal and affected alleles.Additionally,the presymptomatic diagnosis in 103 family members at risk for HD disclosed that 35 individuals had HD alleles,which were- in accordance with the pedigree analysis and clinical investigation.All these results indicated that the dynamic mutation in IT15 gene was responsible for the genetic defect in the Chinese HD patients and that a correlation existed between the numbers of(CAG)n repeat and the onset age of the disease.All-of these provide valuable data for HD molecular diagnosis,ge- netic counselling and genetic health.
作者
Zeng Yitao Mao Yuehua Chen Meijue Ren Zhaorui Zhou Gang Huang Shuzhen (Shanghai Institute of Medical Genetics,Shanghai Children’s Hospital,Shanghai 200040,P.R.China) Wang Xiuying~① Yie Wenghu~② Zhao Xiangzhi~③ (①Xuzhou Medical College,Xuzhou,JiangSu,P.R.China) (②Anhui Medical University,Aanhui,P.R.China) (③Henan Psychiatrical Institute,Zhengzhou,P.R.China)
基金
the High Technology Research Development Programme of China
