Collie Eye Anomaly (CEA), also known as choroidal hypoplasia, is a heritable disorder that can result in abnormal development of inner structures of the eye. This genetic variant is associated with CEA in multiple breeds.
Progressive retinal atrophy (PRA) is characterized by degeneration of the retina resulting in progressive vision loss leading to total blindness. This Shetland Sheepdog type PRA is caused by a mutation in the CNGA1 gene. This is not the only cause of PRA in the breed.
Multidrug Sensitivity is caused by a deletion in the ABCB1 gene, also known as the multidrug resistance 1 (MDR1) gene, and is characterized by neurotoxicity following the use of certain common drugs. Dogs with two copies of MDR1 will exhibit multidrug sensitivity. Some dogs with 1 copy of MDR1 may also exhibit multidrug sensitivity.
Progressive rod-cone degeneration (PRCD) is an inherited form of late-onset progressive retinal atrophy (PRA) that has been identified in many dog breeds.
A variant in the Keratin-71 gene is associated with curly hair in dogs. Dogs with this curl variant have curly coats or wavy coats depending on how many copies of the variant they possess.