KBG syndrome, caused by loss-of-function of the Ankyrin repeat domain-containing protein 11 gene (ANKRD11), is a neurodevelopmental disorder (NDD) named after the surname initials (K, B and G) of the first three families with KBG syndrome, and first described by Herrmann et al. (1975). The gene discussed is ANKRD11; the disease is KBG syndrome.