Recent study reported that the decrease of gonadotropin secretion led to partial lack of pubertal development in mammalian that case causes by congenital hypogonadotropic hypogonadism (Bouligand et al. 2010) and GnRH1 gene validating definitively the vital function in mammalian pubertal development and reproduction process. The gene discussed is GNRH1; the disease is hypogonadotropic hypogonadism.