To date, 21 genes associated with KS/nIHH have been identified, namely, KAL1, FGFR1, FGF8, PROKR2, PROK2, CHD7, FGF8, GNRHR, KISS1R, NELF, TAC, TAC3R, GNRH1, KISS1, WDR11, HS6ST1, SEMA3A, SPRY4, IL17RD, DUSP6, FGF17, and FLRT3. The gene discussed is SPRY4; the disease is hypogonadotropic hypogonadism.