ZIC3 and syndromic X-linked intellectual disability 5: While the former disorders are not typically associated with significant dysmorphisms, hydrocephalus may be part of the phenotypic spectrum of many other clinically recognizable syndromes, such as Pettigrew syndrome (MIM# 304340), VACTERL-H (MIM# 314390) due to ZIC3 mutations or RASopathies (i.e., Noonan syndrome, cardio-facio-cutaneous syndrome, Costello syndrome) (59).