Hypogonadotropic Hypogonadism 15 with or Without Anosmia, also known as hh15, is related to hypogonadotropic hypogonadism 2 with or without anosmia. An important gene associated with Hypogonadotropic Hypogonadism 15 with or Without Anosmia is HS6ST1 (Heparan Sulfate 6-O-Sulfotransferase 1). Affiliated tissues include pituitary and testes, and related phenotypes are small pituitary gland and anosmia