Cerebellar Purkinje's cell degeneration and coat color dilution in a family of Rhodesian Ridgeback dogs.

A syndrome of cerebellar Purkinje's cell degeneration and coat color dilution was diagnosed in a family of Rhodesian Ridgeback dogs. One male and 1 female from the same litter and 1 female from a different litter were evaluated for growth retardation, inability to ambulate, and progressive ataxia. On physical examination, lateral recumbency, severe ataxia, tremors, and diluted coat color were identified. Littermates with nondiluted coat color were neurologically normal. Results of routine laboratory tests, urine metabolic screenings, and karyotype analyses were normal. Histopathologic abnormalities at necropsy included cerebellar Purkinje's cell degeneration, reduced granular cell layer thickness, and uneven distribution of macromelanosomes within hair shafts. Pedigree analysis suggested an autosomal recessive mode of inheritance. This is the first description of a genetic syndrome affecting the central nervous system and associated with coat color dilution in dogs.