title: Familial cerebellar ataxia presenting with down beat nystagmus.
abstract: Two brothers are described who during their fourth decade presented with isolated down beat nystagmus and later developed a progressive cerebellar ataxia. The nature of this unusual oculomotor disorder and its rare occurrence in other inherited conditions are discussed.
mesh_terms: D000328:Adult; D002524:Cerebellar Ataxia / Q000150:complications / Q000235:genetics*; D005808:Genes, Recessive; D006801:Humans; D008297:Male; D008875:Middle Aged; D009759:Nystagmus, Pathologic / Q000150:complications / Q000235:genetics*; D010375:Pedigree