Pituitary dwarfism / Combined pituitary hormone deficiency (CPHD)
In dogs, pituitary dwarfism is the most common manifestation of combined pituitary hormone deficiency. It is characterized by a combined deficiency of growth hormone (GH), thyroid stimulating hormone (TSH), prolactin, and the gonadotropins. The hormone deficiencies can lead to a wide range of clinical manifestations, but the most common ones are marked growth retardation, retention of lanugo or secondary hairs (so-called puppy hair coat) with concurrent lack of primary or guard hairs, and bilateral symmetrical alopecia. It is caused by a mutation in a gene coding for LHX3 protein, a member of protein family of DNA-binding transcription factors, which is an essential regulator of pituitary development.
Voorbij, A.M.W.Y., van Steenbeek, F.G., Vos-Loohuis, M., Martens, E.E.C.P., Hanson-Nilsson, J.M., van Oost, B.A., Kooistra, H.S., and Leegwater, P.A. (2011). A contracted DNA repeat in LHX3 intron 5 is associated with aberrant splicing and pituitary dwarfism in German shepherd dogs. PLoS ONE 6, e27940.
Voorbij, A. m. w. y., Leegwater, P. a., and Kooistra, H. s. (2014). Pituitary Dwarfism in Saarloos and Czechoslovakian Wolfdogs is Associated with a Mutation in LHX3. J Vet Intern Med 28, 1770–1774.
Andresen, E. (1976.): Pituitary dwarfism in German shepherd dogs: additional evidence of simple, autosomal recessive inheritance. Nord Vet Med. 1976 Oct;28(10):481-6.