Multiple Retrocopies Recently Derived within Canids.

Two transcribed retrocopies of the fibroblast growth factor 4 () gene have previously been described in the domestic dog. An retrocopy on chr18 is associated with disproportionate dwarfism, while an retrocopy on chr12 is associated with both disproportionate dwarfism and intervertebral disc disease (IVDD). In this study, whole-genome sequencing data were queried to identify other retrocopies that could be contributing to phenotypic diversity in canids.

A RAPGEF6 variant constitutes a major risk factor for laryngeal paralysis in dogs.

Laryngeal paralysis (LP) is the inability to abduct the arytenoid cartilages during inspiration, resulting in a partial to complete airway obstruction and consequent respiratory distress. Different forms of LP with varying age of onset exist in dogs. Hereditary early onset forms were reported in several dog breeds.

Phenotypic Effects of Retrogenes on Intervertebral Disc Disease in Dogs.

Two retrogenes on chromosomes 12 (12-RG) and 18 (18-RG) contribute to short-limbed phenotypes in dogs. 12-RG has also been associated with intervertebral disc disease (IVDD). Both of these retrogenes were found to be widespread among dog breeds with allele frequencies ranging from 0.

An ADAMTS3 missense variant is associated with Norwich Terrier upper airway syndrome.

In flat-faced dog breeds, air resistance caused by skull conformation is believed to be a major determinant of Brachycephalic Obstructive Airway Syndrome (BOAS). The clinical presentation of BOAS is heterogeneous, suggesting determinants independent of skull conformation contribute to airway disease. Norwich Terriers, a mesocephalic breed, are predisposed to Upper Airway Syndrome (UAS), a disease whose pathological features overlap with BOAS.