[Normosmic idiopathic hypogonadotropic hypogonadism with GnRH receptor mutation(review)]

Mutations in gonadotropin releasing hormone receptor(GnRHR) gene(chromosome location, 4q21.2) cause autosomal recessive idiopathic hypogonadotropic hypogonadism (IHH) without anosmia. The spectrum of phenotypes is much broader, the mechanism of which still remains clarified yet. The prevalence may be 2.2% in all families with IHH, but 7.1% in families in which the affected female is present. The frequency may be common in familial case(40%) and infrequent in general sporadic cases(16.7%). Functional mutations of the GnRHR are distributed widely throughout the protein, although the hot spots are Gln(106) Arg and Arg (262) Gln. The same mutations cause different gonadotropin secretion capability, in which hyperstimulated pulsatile GnRH treatment could bring ovulation and pregnancy in some cases.