ESPE Abstracts

Background: The immunoglobulin superfamily member 1 (IGSF1) gene encodes a plasma membrane glycoprotein enriched in pituitary and testes. Loss-of-function mutations in IGSF1 cause an X-linked syndrome of central hypothyroidism (CeH), macroorchidism, and delayed pubertal rise of testosterone despite normal timing of testicular growth. This syndrome was discovered in patients with CeH; therefore, it is presently unknown whether IGSF1 mutations also cau...