Frequency of spinocerebellar ataxia types 1, 2, 3, 6, 7 and dentatorubral pallidoluysian atrophy mutations in Korean patients with spinocerebellar ataxia

Abstract

Autosomal dominant cerebellar ataxias (ADCAs) are a heterogeneous group of disorders characterized by degenerative symptoms in the cerebellum, spinal cord, and brain stem. Six different genes have been reported to be associated with ADCA, and the length of trinucleotide repeats of these genes is correlated with the age at onset and severity of symptoms. Although there are strong hereditary effects in these disorders, most of the studies carried out in heterogeneous populations and in small groups obscure the true incidence of these diseases. We examined the frequency of six types of ADCAs in 87 unrelated Korean patients with progressive ataxia and compared the results to the frequencies in other ethnic groups. Spinocerebellar ataxia (SCA) type 2 was the most frequent hereditary ataxia (12.6%) and types 3 and 6 accounted for 4.6% and 6.9% of ataxia patients, respectively. Dentatorubral pallidoluysian atrophy was also found in three patients (3.4%). No instances of SCA types 1 or 7 were detected. These findings show the striking contrast to the white population and a difference from Japanese findings. Our results demonstrate that dentatorubral pallidoluysian atrophy should be included in the differential diagnosis of Korean patients with spinocerebellar ataxia, and that there are strong hereditary effects in patients with ADCAs.

Spectrum and prevalence of autosomal dominant spinocerebellar ataxia in Hokkaido, the northern island of Japan: a study of 113 Japanese families

“…In the Nagano district of Japan, DRPLA was reported to be the second most frequent of the ADCA subtypes (10%) (Shimizu et al 2004). There have also been a few reports of DRPLA from Korea (Jin et al 1999), USA (Brunetti-Pierri et al 2006) and Canada (Espay et al 2006). The expanded repeat ranges and the clinical features of the SCA6, SCA3, SCA1, SCA2, and DRPLA families were similar to those reported previously (data not shown) (Zhuchenko et al 1997;Kawaguchi Y et al 1994;Orr et al 1993;Sanpei et al 1996;Koide et al 1994).…”

A Genetic Epidemiological Study of Spinocerebellar Ataxias in Tottori Prefecture, Japan

“…Expansions of CAG, CTG and GAA repeats exist in various types of SCA, including SCA1 [1], SCA2 [2], SCA3 [3], dentatorubral-pallidoluysian atrophy (DRPLA) [4], SCA6 [5], SCA7 [6], SCA8 [7] and Friedreich's ataxia (FRDA) [8]. The widespread availability of direct gene testing for these diseases has permitted the determination of the frequency of inherited SCA genotypes in heterogeneous populations worldwide [9][10][11][12][13][14][15]. However, these reports are biased because of laboratory-based sampling, including patient with genetically confirmed diagnoses, thus masking the true frequency or prevalence of these diseases.…”

Determination of Genotypic and Phenotypic Characteristics of Friedreich’s Ataxia and Autosomal Dominant Spinocerebellar Ataxia Types 1, 2, 3, and 6

“…Considering not only FA cases described above, but also SCA1, SCA2, SCA3, and SCA6 cases studied together with laboratory tests, though there are exceptional examples, it was noted that the most commonly seen SCA type globally was SCA3 (39,40,41).…”