Abstract
Congenital normosmic isolated hipogonadotropic hypogonadism (IHH) is caused by defects on the synthesis, secretion or action of GnRH. The most common genetic causes of IHH are inactivating mutations in the pituitary GnRH receptor (GnRHR). The first mutations in the GnRHR gene were described by de Roux et al. in 1997 and, since then, many other defects have been reported in this gene. Cos…