Korean J Lab Med.  2003 Feb;23(1):60-66.

Distribution of Alleles and Clinical Manifestation in Patients with Progressive Ataxia Caused by Trinucleotide Repeat Expansion

• Lee SG
• Ki CS
• Kim JW
• Suh JS

Abstract

BACKGROUND
Trinucleotide repeat (TNR) expanded disorders represent a novel class of human mutations, which are characterized by abnormal elongation of the triplet repeat sequence in the human genome and is caused by heritable DNA instability. The aim of this study is to determine the relative frequency, distribution of alleles, and the clinical manifestation of TNR expanded disorders in Korean patients with progressive ataxia. METHODS: A total of 76 clinical specimens that were suspicous of hereditary cerebellar ataxia were submitted from January 1999 to August 2001 and tested for TNR expanded disorders by PCR analysis. RESULTS: Spinocerebellar ataxia (SCA) type 1 was the most common hereditary ataxia (5.3%), while SCA2, SCA3, SCA6, SCA7, and dentatorubral and pallidoluysian atrophy (DRPLA) represented 2.6%, 3.9%, 2.6%, 2.6%, and 1.3% of progressive ataxia patients, respectively. This result is different from previous reports concerning Caucasian, Chinese and Koreans. CONCLUSIONS: This study may provide the basis for the study of TNR expanded disorders in Korean patients. To elucidate the prevalence and frequencies of mutation types in Koreans, a large scale study should be performed.

Keyword

Frequency; Clinical manifestation; Trinucleotide repeat (TNR) expanded disorders; Spinocerebellar ataxia (SCA)

MeSH Terms

Alleles*
Asian Continental Ancestry Group
Ataxia*
Atrophy
Cerebellar Ataxia
DNA
Genome, Human
Humans
Polymerase Chain Reaction
Prevalence
Spinocerebellar Ataxias
Spinocerebellar Degenerations
Trinucleotide Repeat Expansion*
Trinucleotide Repeats
DNA