SHANK3 and Intellectual disability: Two studies conducted a systematic array-CGH analysis of catatonic patients hospitalised in child psychiatry and adult psychiatry units and found one case of intragenic deletion of the SHANK3 gene among 37 catatonic adolescents, i.e., almost 3%, and two cases among 15 catatonic adults with intellectual disability, i.e., 13% (68, 93).