Diseases of G-Protein-Coupled Signal Transduction Pathways: The Mammalian Visual System as a Model

G-protein-coupled signaling systems play a role in a diversity of normal physiological functions. Logically, one might predict that mutations in genes encoding any one of the G-protein subunits, G-protein-coupled receptors, or effector proteins of a given signaling pathway could lead to disease. Mutations of G-protein-coupled signaling proteins known to cause human diseases are reviewed here, with a primary emphasis on the mammalian phototransduction system.