Spinocerebellar ataxia type 23 is an uncommon SCA subtype in the Chinese Han population

► Mutations in PDYN gene were firstly screened in 305 unrelated Chinese Han ataxia patients by PCR and DNA direct sequencing. ► A probable novel single nucleotide polymorphism (c.255G>A, p.Lys85Lys) was found. ► It suggests that SCA23 is a rare subtype in mainland China.