GH exerts pleiotropic effects on growth and metabolism through the GH receptor. A deficiency in the GH receptor gene is thus associated with GH resistance and dwarfism. Complete GH resistance in humans, or Laron syndrome, has been associated with numerous inherited defects in the GH receptor, including point mutations, complete or partial gene deletions, and splice site alterations. Analysis of the GH receptor genes of these patients has provided considerable insight into structure-function relationships of the GH receptor. However, the relative rarity of this disease and the obvious difficulties involved in human research have prompted a search for an animal model of GH resistance. Numerous models have been proposed, including the sex-linked dwarf chicken, the guinea pig, and the Laron mouse. In this review, the characteristics and etiology of Laron syndrome and these animal models will be discussed. The insight provided by these disorders into the roles and mechanism of action of GH will also be reviewed.

This article has been cited by other articles:

				E. de Graaf-Roelfsema, W. Back, H. A. Keizer, T. A. E. Stout, and J. H. van der Kolk Normal function of the hypothalamic-pituitary growth axis in three dwarf Friesian foals Vet Rec., September 26, 2009; 165(13): 373 - 376. [Abstract] [Full Text] [PDF]

				G. O. Ramirez-Yanez, J. R. Smid, W. G. Young, and M. J. Waters Influence of growth hormone on the craniofacial complex of transgenic mice Eur J Orthod, October 1, 2005; 27(5): 494 - 500. [Abstract] [Full Text] [PDF]

				C. W. E. Meyer, D. Korthaus, W. Jagla, E. Cornali, J. Grosse, H. Fuchs, M. Klingenspor, S. Roemheld, M. Tschop, G. Heldmaier, et al. A Novel Missense Mutation in the Mouse Growth Hormone Gene Causes Semidominant Dwarfism, Hyperghrelinemia, and Obesity Endocrinology, May 1, 2004; 145(5): 2531 - 2541. [Abstract] [Full Text] [PDF]