Copy Number Variations and Neuropsychiatric Diseases

Abstract

Copy number variants (CNVs) are submicroscopic deletions and duplications of deoxyribonucleic acid (DNA) segments, which can have a high impact on gene expression. Methods to explore CNVs include array comparative genomic hybridisation, single‐nucleotide polymorphism microarrays and whole genome sequencing. Rare CNVs are strongly associated with neuropsychiatric diseases including autism spectrum disorder, schizophrenia, bipolar disorder and disruptions to some specific loci have been related to more than one disorder. The chromosome 22q11.21 deletion is so far the locus identified with the highest risk, 82% for any psychiatric disorder. De novo copy number events, those present in cases but not in their parents, also have a significant risk for any of these disorders, with an overall risk of 13% to develop a neuropsychiatric disorder if present anywhere in the genome. Key Concepts: Copy number variants are so far the most potent sources of genetic risk for neuropsychiatric disease. Rare and de novo events are associated with neuropsychiatric disorders.