Spinocerebellar ataxia type 10 is rare in populations other than Mexicans

Abstract

Spinocerebellar ataxia type 10 (SCA10) is an autosomal dominant neurodegenerative disease characterized by progressive ataxia and seizures that was initially identified in two Mexican families.1-3⇓⇓ It belongs to a heterogenous group of diseases known as autosomal dominant cerebellar ataxias (ADCA). In ADCA, expanded CAG repeats coding for polyglutamine tracts cause SCA1, 2, 3, 6, 7, and 17, whereas expansions of CTG and CAG repeat in noncoding region are considered pathogenic in SCA8 and 12, respectively.4 The chromosomal location of SCA 4, 5, 11, 13, 14, and 16 have been determined although their mutations remain to be identified.4 We recently determined that the SCA-10 mutation is an unstable expansion of a pentanucleotide (ATTCT) repeat in intron 9 of a novel gene, SCA10 , on chromosome 22q13.3. Although the number of the repeat ranges from 10 to 22 in more than 300 healthy individuals,5 …