FGFR1 and holoprosencephaly: Clinical manifestations of FGFR1 alterations are very heterogeneous and can result in two autosomal dominant syndromes that can be associated with HPE: Kallmann syndrome, which is characterized by hypogonadotropic hypogonadism and anosmia; and Hartsfield syndrome, which is associated with HPE, ectrodactyly, cleft lip and palate [74,75,76,77].