Journal of Genetic Medicine  2007;4(1):84-87

Rapid prenatal diagnosis of spinocerebellar ataxia type 3 by using fluorescent PCR.

Do Jin KIM 1 ; So Yeon PARK ; Mi Jin KIM ; Moon Hee LEE ; Sung Han SHIM ; Hyun Mee RYU

Affiliations

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Keywords

Prenatal diagnosis; Spinocerebellar ataxia Type 3; Fluorescent probes

Country

Republic of Korea

Language

English

Abstract

Spinocerebellar Ataxia Type 3 (SCA3) is a rare autosomal dominative disorder in which one of the neurodegenerative disorders is caused by a CAG repeat expansion on chromosome 14q32.1. The age at onset of disease is related to the size of the expanded CAG repeat. We present the prenatal diagnosis of SCA3 in a woman whose husband was known to carry an unstable CAG repeat expansion in the MJD gene. The diagnosis was made using PCR with a fluorescent probe for an expanded MJD allele. The normal ranges of (CAG)n of SCA3 are 14~38 repeats. The husband, who had a family history of SCA3, has an expanded allele of 69 CAG repeats with a normal allele of 27 repeats. His wife had two normal alleles with 26 and 32 CAG repeats. The fetus had two normal alleles with 26 and 27 CAG repeats; consequently, the baby was healthy. We report a case of prenatal diagnosis of SCA3 using a fluorescent PCR which is rapid and accurate.