Pituitary Dwarfism (Shepherd Type)
Affected Genes: LHX3
Inheritance: Autosomal Recessive
Variant(canFam6):
chr9:48503009-48503015: 7 bp deletion GCGCCCC
Breed: Czechoslovakian Wolfdog
German Shepherd Dog
Saarloos Wolfdog
Shiloh Shepherd
Tibetan Terrier
White Shepherd Dog
General Information: Pituitary Dwarfism (PD) (Shepherd Type) affects German Shepherds and related breeds, manifesting as significantly reduced growth due to an underdeveloped pituitary gland. Dogs with this condition appear notably smaller than their littermates and retain their puppy coats for an abnormally long duration. Symptoms often include alopecia (loss of hair), hyperpigmentation of the skin, and delayed or absent sexual maturation. The condition also predisposes affected dogs to various metabolic and endocrine disorders, such as kidney disease and hypothyroidism. Despite normal intelligence, affected dogs may show reduced energy levels. Early diagnosis is crucial but challenging, as visible signs can be subtle in the initial months.
How to Read Your Dog's Test Results for this Genetic Variant:
Two Variants Detected: Dog Likely Affected
One Variant Detected: Dog Unlikely Affected
No Variants Detected: No Effect
Gene / Testing Information: Genetic testing for Pituitary Dwarfism (PD) in German Shepherds focuses on the LHX3 gene mutation, which is transmitted in an autosomal recessive manner. This means that for a dog to be affected by this condition, it must inherit two copies of the mutated gene, one from each carrier parent. Carriers do not exhibit symptoms but can pass the defective gene to their offspring. When two carriers are bred, there is a 25% chance of producing affected pups and a 50% chance of producing another carrier. To prevent the perpetuation of this debilitating condition, responsible breeding practices are crucial, which includes genetic testing of breeding dogs to identify carriers and manage breeding pairs accordingly. Avoid breeding carriers together to reduce the risk of producing affected offspring.
References:
Voorbij AMWY, Leegwater PA, Kooistra HS. Pituitary Dwarfism in Saarloos and Czechoslovakian Wolfdogs is Associated with a Mutation in LHX3. J Vet Intern Med. 2014;28(6):1770-1774.
Voorbij AMWY, van Steenbeek FG, Vos-Loohuis M, Martens EECP, Hanson-Nilsson JM, van Oost BA, Kooistra HS, Leegwater PA. A contracted DNA repeat in LHX3 intron 5 is associated with aberrant splicing and pituitary dwarfism in German shepherd dogs. PLoS One 2011; 6(11):e27940.