Inborn errors of signal transduction: mutations in G proteins and G protein-coupled receptors as a cause of disease.

A vast array of neurotransmitters, polypeptide hormones and other extracellular signalling molecules utilize G protein-coupled pathways for transmembrane signalling. In recent years, mutations in G protein-coupled receptors and in G protein alpha subunits have been identified as the cause of a variety of human diseases. Both loss and gain of function mutations have been described in disorders such as Albright hereditary osteodystrophy, nephrogenic diabetes insipidus, McCune-Albright syndrome, and familial male precocious puberty. Identification of mutations in G protein-coupled receptors and in G proteins in human diseases has provided unique insights into G protein-coupled signal transduction, has important implications for diagnosis and potentially for treatment, and should stimulate the search for additional defects in G protein-coupled signal transduction in other diseases.