A 22q13.33 duplication harbouring the SHANK3 gene: does it cause neuropsychiatric disorders?

A young man with neuropsychiatric problems has a small 22q13.33 duplication. We suggest this causes his condition. His disorder may represent a 22q13.33 behavioural phenotype. In childhood, he was diagnosed with mild intellectual disability. He was later diagnosed with Tourette syndrome, atypical autism spectrum disorder and bipolar disorder. Lithium seems effective in treating his affective symptoms. He has mild dysmorphic features, full lips and protruding ears. An array comparative genomic hybridisation showed a 300 kb duplication. The duplication harbours several genes, notably SH3 and multiple ankyrin repeat domain 3 (SHANK 3). The small size helps focus on a critical region for a 22q13.33 duplication syndrome. Mutations, deletions and duplications should be kept in mind as causes of neuropsychiatric disorders, especially in a patient with dysmorphic traits. © BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.