DRD2 and Retinal dysplasia: The occurrence of retinal folds in dogs, also called canine retinal dysplasia, has been observed in non-syndromic (sporadic) multifocal retinal dysplasia and in syndromic multifocal retinal dysplasia among Labrador retrievers and Samoyeds harboring the drd1 and drd2 (dwarfism with retinal dysplasia 1 and 2) mutant alleles [52].