Recently, the missense mutation KCNJ10:c.627C > G was shown to be associated with the spinocerebellar ataxia (SCA) in JRT and related Russell group of terriers, whereas the missense mutation CAPN1:c.344G > A was associated with late onset ataxia (LOA) in PRT. The gene discussed is KCNJ10; the disease is autosomal dominant cerebellar ataxia.