Disease Ontology ID: DDTO:0000892

Disease Description: This condition develops in some, but not all dogs that have been bred for unusual coat colour, especially "fawn" (a dilution of a  normally red or brown coat) or "blue" ( a dilution of the normal black and tan coat colour). Alopecia means hairlessness - affected dogs have a poor, patchy haircoat progressing to widespread permanent hair loss. At the cellular level, there are abnormalities of the hair follicles and uneven clumping of pigment (melanin) granules in the hair shafts in affected areas

Inherit Mode: The inheritance is unclear. The condition is thought to be due to the interaction of different factors at the gene position for colour. It is not simply determined by the genes at that locus, because not all dogs with colour dilution develop coat problems.

Disease Symptom: Dogs with this condition are born with a normalhaircoat. Those withlighter blue or fawn hair coats usually start to show changes by 6months while in dogswith darker steel blue coats, the changes may not be evident until 2or 3 years of age.Your dog will experience hair loss and dry skin. Sometimes theearliest sign is arecurring bacterial infection (folliculitis), generally on the back,where you will seesmall bumps which are infected hair follicles. This clears uptemporarily withantibiotics, but the affected area is very slow to regrow hair, orremains hairless. Hair loss is usually first apparent on the backand by 2 or 3 yearshas spread over all the light coloured areas of the body. The exposedskin is often scalyand is susceptible to sunburn or extreme cold. Your dog's health isnot otherwise affectedby this condition.

Disease Cause: -

Disease Diagnose: Your veterinarian may suspect this disorder if yourdog has typicalhaircoat changes and is an unusual colour for the breed. The diagnosisis confirmedthrough microscopic examination of plucked hairs or a skin biopsy. Thelatter is a simpleprocedure, done with local anesthetic, in which your veterinarianremoves a small sampleof your dog's skin for examination by a veterinary pathologist. Thebiopsy will showchanges characteristic of this condition.

Treat Method: Your dog can lead a normal healthy life withperiodic symptomatictreatment as needed - moisturizing rinses for dry scaly skin orantibiotics for bacterialinfections. Since early hair loss occurs due to breakage,you may be able toslow the rate of loss by avoiding harsh shampoos and vigorousgrooming. For the veterinarian: Therehave been some earlyreports of hair regrowth using etretinate treatment . (See resourcebelow.)

Breeder Advice: Affected dogs, their parents and siblings shouldnot be used forbreeding. The condition can be entirely avoided by the use ofnon-colour-diluted dogs inbreeding programmes.

Disease Description Source: Link