Affected gene: PDP1
 Inheritance: Autosomal recessive
 Mutation: CanFam3.1 chr29 g.38788845 C>T
 OMIA link: 001406-9615
 Breeds appropriate for testing: Clumber and Sussex Spaniels
Symptoms:
The first clinical signs generally appear between 4 and 6 weeks of age. Ocular abnormalities may include cataracts, vitreous syneresis, and retinal detachment. Retinal dysplasia or degeneration, as well as lens coloboma, may also be observed. Disease expression is variable, ranging from asymptomatic forms to complete loss of vision. Skeletally, affected dogs frequently exhibit limb dwarfism, shortening of the ulna, bowing of the radius, and joint problems such as osteoarthritis and hip and elbow dysplasia.