Of these, we focused on 3 well-established exemplar genes: ANKRD11 (KBG syndrome; n = 79),15 which has the largest number of DDD diagnoses; CTNNB1 (neurodevelopmental disorder with spastic diplegia and visual defects; n = 30),16 in which there is a clinical imperative for ophthalmic surveillance; and NSD1 (Sotos syndrome; n = 20),17 in which the highest proportion of DDD probands (65%) had medical interventions after a diagnosis. This evidence concerns the gene NSD1 and KBG syndrome.