Molecular genetic diagnosis and clinical analysis of spinocerebellar ataxia type7

Abstract

Abstract: Objective To study the molecular genetic diagnosis and clinical cha ra cteristics of spinocerebellar ataxia type 7 (SCA7).Methods This study included 43 patients with autosomal dominant SCA from 36 families, 38 sporadic SCA patien ts, 60 healthy individuals from the SCA families and 44 normal controls without family SCA history. The SCA7 (CAG)n muta-tions were detected by PCR, denaturing polyacrylamide gel electrophoresis and silver staining technique. The abnormal a llele fragments were sequenced by ABI373 DNA sequencing machine.Results Normal alleles of SCA7 were found to have 9 to 19 CAG repeats. Two familial SCA and on e sporadic patients were identified by detecting the presence of abnormal CAG-re -peat expansion in the SCA7 alleles, which was confirmed by DNA sequencing. The repeats of CAG were 65, 65, and 63 re-spectively. Conclusions Abnormal CAG expan sion is the pathogenic cause of SCA7. Molecular genetic analysis is effective f or the diagnosis of SCA, prediction of presymptomatic patients and genetic couns eling.

CLC Number:

XIE Qiu-you, LIANG Xiu-ling, LI Xun-hua, FENG Yan-qing. Molecular genetic diagnosis and clinical analysis of spinocerebellar ataxia type7[J]. Journal of Southern Medical University, 2004, 24(01): 62-65.

References

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