Leydig-Cell Tumors Caused by an Activating Mutation of the Gene Encoding the Luteinizing Hormone Receptor

Abstract

The receptor for luteinizing hormone and chorionic gonadotropin plays a major part in normal and abnormal reproductive function.1–4 In males, activation of the receptor regulates the development and function of Leydig cells.5 Testosterone secreted by Leydig cells promotes male sexual differentiation, pubertal androgenization, and fertility. The human luteinizing hormone receptor is a G protein–coupled receptor with a transmembrane domain composed of seven segments. Activation of the receptor by luteinizing hormone leads to activation of Gs, the G protein that is coupled to adenylyl cyclase, and to an increase in cyclic AMP (cAMP). High concentrations of luteinizing hormone . . .