Initial Genome-Wide Case-Control Study for Genetic Background of Retinal Dysplasia in Czechoslovakian Wolfdog

Retinal dysplasia is a genetically heterogeneous ocular disorder in dogs, characterized by abnormal retinal development, resulting in a range of visual impairments from mild to complete blindness. The objective of this study was to investigate the prevalence and genetic basis of retinal dysplasia in the Czechoslovakian Wolfdog breed. An ophthalmic examination was conducted on a cohort of 117 Czechoslovakian Wolfdogs, which revealed a prevalence of multifocal retinal dysplasia of 5.13%. A genome-wide case-control association study was conducted on a subset of 36 adult dogs to explore the underlying genetic architecture of multifocal retinal dysplasia in this breed. The GWAS identified a suggestive association with a locus on canine chromosome CFA37. The strongest association signal for SNP marker BICF2G630130992 (p = 1.29 × 10^-6) was identified in the first intron of the CYP27A1 gene, which encodes a cytochrome P450 enzyme involved in vitamin D metabolism and potentially retinal function. The region of CFA37 contains several other genes that have been previously implicated in ocular development and disease. Further studies utilizing next-generation sequencing and functional analyses are required to validate these findings, identify the causative variants, and fully elucidate the genetic architecture of retinal dysplasia in this breed.