Letters to the Editor SCA19 and SCA22: evidence for one locus with a worldwide distribution

We read with interest the paper by Ming-Yi Chung and colleagues (Chung et al., 2003). In this paper, the authors characterized a four-generation Chinese pedigree with an autosomal dominant phenotype for cerebellar ataxia (ADCA). Their genome-wide linkage study suggested link-age to a locus on chromosome 1p21-q23. The authors stated that the form of ADCA found in this family is distinct from other spinocerebellar ataxias (SCA) and designated this SCA as spinocerebellar ataxia type 22 (SCA22). However, this locus was previously assigned to SCA19 by the HUGO Gene Nomenclature Committe