Lexicon

Golden Retriever Muscle Dystrophy (GRMD) is a degenerative muscle disease in which muscle fibre degeneration and necrosis occur due to a malformation of the dystrophin protein. Affected dogs suffer from muscle wasting, weakness and feeding difficulties. The poor quality of life often leads to euthanasia.

The disease occurs in Golden Retrievers and is inherited in an X-linked recessive manner.

Synonym: X-linked muscular dystrophy, Duchenne muscular dystrophy, Dystrophin-deficient muscular dystrophy

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Also in the Golden Retriever B package (DRC P4)

Due to the Grey mutation, normally coloured foals first turn grey and later white. They slowly "lose" their colour, as pigment-producing cells gradually stop to produce pigment and the hairs that grow back have less and less colour pigments and eventually none at all. Transitions patterns such as "dapple grey" and "flea-bitten" etc. develop.

The responsible gene (STX17) is involved in cancer pathways. The duplication that causes the grey colour also predisposes grey horses to developing melanoma.

The dog has a light face mask with so-called "widow's peak". This colour pattern is caused by the Eg allele of the extension locus.

See: Extension (Coat colour E-Locus Dog)

Hair length is a trait in many dog breeds, which is important in the selection of intended matings. There is usually a short coat type and a long coat type.

Which genetic type the dog has, i.e. which coat length it develops, can be determined by a genetic test (FGF5 gene).

This coat structure occurs in many different breeds.

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Hairlessness (ectodermal dysplasia) results in bald (hairless) patches all over the body. The trait occurs in a few breeds, e.g. Chinese Crested Dog and Mexican Naked Dog. It is homozygous lethal. Dogs with two copies of the mutated gene die before birth.

Harlequin dogs show black patches on a white base coat. It is a modified version of the Merle colouration. This means that all dogs showing the Harlequin pattern in the phenotype also have one copy of the Merle mutation. Dogs without the mutation for Merle (m/m), can be carriers for Harlequin.

The colour is caused by the H allele of the H locus. Homozygous animals (H/H) die before birth.

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Hereditary Equine Regional Dermal Asthenia (HERDA) is caused by the presence of abnormal collagen in the skin. This results in skin detachment, severe lesions, ulcerations and wound healing problems.

The disease occurs in the Quarter Horse and related breeds. It is inherited autosomal recessively.

Synonym: Ehlers-Danlos syndrome, hyperelastosis cutis

Hereditary Nasal Parakeratosis (HNPK) is a differentiation disorder of the skin cells (keratinocytes) in the area of the dog's nose. Affected dogs show firm scabs on the upper nose leather and thus a risk of cracks and fissures on the nose.

The pre-damaged skin can be more easily infected by pathogens, which can lead to complications. The animals are otherwise healthy.
The disease occurs in the Labrador Retriever. The inheritance is autosomal recessive.

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Also in the Labrador Retriever A package (DRC P1)

Hoof Wall Separation Disease (HWSD) is characterized by a defect in the connective tissue of the hoof wall. Affected animals have hooves that can be brittle and crack easily. The mutation was originally identified in Connemara ponies but has not also been found in Tinkers, Cobs, American Miniature Horses, and German Riding Ponies. It has an autosomal recessive mode of inheritance.

Genetic Test: available in Shop

In hydrocephalus, cerebrospinal fluid accumulation in the brain leads to enlarged skull and death of the foal. The disease occurs in Friesian horses and is inherited autosomal recessively.