As the mouse nasal embryonic LHRH factor gene (Nelf) encodes a guidance molecule for the migration of the olfactory axon and gonadotropin-releasing hormone neurons, its human homolog, NELF, is a candidate gene for Kallmann syndrome, a disease of idiopathic hypogonadotropic hypogonadism (IHH) with anosmia or hyposmia.
Nasal embryonic LHRH factor (NELF) and early B-cell factor 2 (EBF2) exons were evaluated in KAL-1/GnRH-R mutation-negative cases (seven KS and five nHH) by sequence analysis but no mutations were identified in the coding regions in these patients.
Even though it is a genotypically and phenotypically heterogeneous clinical disease, there are some key genes related to KS (KAL1, FGFR1 (KAL2), GNRHR, KISSR1 (GPR54), GNRH1, NELF and PROK2).