Breeds Affected: Cavalier King Charles Spaniel
Samples Accepted: Blood, Buccal Swabs
Disease Information: Dry Eye Curly Coat Syndrome is also known as Congenital Keratoconjunctivitis Sicca and Ichthyosiform Dermatosis, CKCSID is a disease in with the hair is abnormal from birth, and eye and nail abnormalities as seen as the animal develops. The coat is rough and/or curly, the eyes do not produce normal amounts of tears, the skin and footpads are thickened (hyperkeritinised). Dental disease is also increased. Due to high incidences of eye ulceration, footpad sloughing and lameness, and skin itchiness and infection, it is not unusual for affected dogs to be euthanized for quality of life reasons.
Inheritance Information: CKCSID is autosomal recessive, meaning that animals with two copies of this allele will be affected. Animals with one copy of the gene will be clinically-normal carriers.
The possible genotypes are:
N/N The dog is normal, and cannot produce affected offspring.
N/ckcsid The dog is a carrier, and can pass the allele on to approximately 50% of any offspring. If bred to another N/ckcsid carrier, approximately 25% of the offspring will be normal, 50% will be carriers, and 25% will be affected.
ckcsid/ckcsid The dog is affected. If bred to a normal animal, 100% of the offspring will be carriers. If bred to an N/ckcsid carrier, 50% of the offspring will be carriers and 50% will be affected.
– Carriers may be bred to normal animals (N/ckcsid x N/N) without any risk of producing affected offspring. The offspring should be tested before breeding to determine if they are carriers or normal.
– Breeding two carriers (N/ckcsid x N/ckcsid) is not recommended due to the possibility of 25% of the offspring being affected.
– Affected animals (ckcsid/ckcsid) should not be used for breeding.
Test Information: This mutation test identifies a single base deletion in exon 5 of the FAM83H gene.
Forman, O.P., Penderis, J., Hartley, C., Hayward, L.J., Ricketts, S.L., Mellersh, C.S.: Parallel Mapping and Simultaneous Sequencing Reveals Deletions in BCAN and FAM83H Associated with Discrete Inherited Disorders in a Domestic Dog Breed. PLoS Genet 8:e1002462, 2012. Pubmed reference: 22253609. DOI: 10.1371/journal.pgen.1002462.
Further information is available at the Online Mendelian Inheritance in Animals website.