A Novel Missense Mutation in the Spectrin Beta Nonerythrocytic 2 Gene Likely Associated with Spinocerebellar Ataxia Type 5

To the Editor：Spinocerebellar ataxia type 5 （SCA5） is a rare autosomal dominant spinocerebellar ataxia.Mutations in the spectrin beta nonerythrocytic 2 gene （SPTBN2） are known to cause SCA5,six of which have been reported,including three missense mutations and three deletion mutations.