Two structural variants, a balanced t(1;11) translocation interrupting the DISC1 gene and a microdeletion at 22q11.2, were the first genetic polymorphisms to show compelling evidence of association with schizophrenia1, 2. More recently, additional microdeletions and microduplications conferring risk of schizophrenia and, in some cases, bipolar disorder have been uncovered3-10. These copy number variants (CNVs) confer high to moderate relative risk, however, because they typically change copy number of multiple genes, and may also affect regulation of genes at their margins, they do not generally implicate individual genes.
