Genomic copy number variants (CNVs) have been strongly implicated in the etiology schizophrenia (SCZ). However, apart from a small number of risk variants, elucidation of the CNV contribution to risk has been difficult due to the very low frequencies of risk alleles, all occurring in less than 1% of patients. We sought to address this obstacle through a collaborative effort unprecedented in psychiatry in which we applied a centralized analysis pipeline to a large SCZ cohort of 21,094 cases and 20,227 controls. A global enrichment of CNV burden is observed in SCZ patients (OR=1.11, P=5.7e-15), and persists after excluding loci implicated in previous studies (OR=1.07, P=1.7e-6). CNV Burden is also enriched for genes associated with synaptic function (OR = 1.68, P = 2.8e-11) and neurobehavioral phenotypes in mouse (OR = 1.18, P= 7.3e-05). While only previously implicated loci surpass strict genome-wide testing correction, we identify “novel” CNVs (BH-FDR < 0.05) that confer both protective and risk effects on SCZ and are predominantly mediated by non-allelic homologous ... (Show More)

Genomic copy number variants (CNVs) have been strongly implicated in the etiology schizophrenia (SCZ). However, apart from a small number of risk variants, elucidation of the CNV contribution to risk has been difficult due to the very low frequencies of risk alleles, all occurring in less than 1% of patients. We sought to address this obstacle through a collaborative effort unprecedented in psychiatry in which we applied a centralized analysis pipeline to a large SCZ cohort of 21,094 cases and 20,227 controls. A global enrichment of CNV burden is observed in SCZ patients (OR=1.11, P=5.7e-15), and persists after excluding loci implicated in previous studies (OR=1.07, P=1.7e-6). CNV Burden is also enriched for genes associated with synaptic function (OR = 1.68, P = 2.8e-11) and neurobehavioral phenotypes in mouse (OR = 1.18, P= 7.3e-05). While only previously implicated loci surpass strict genome-wide testing correction, we identify “novel” CNVs (BH-FDR < 0.05) that confer both protective and risk effects on SCZ and are predominantly mediated by non-allelic homologous recombination (NAHR). Our combined data find genome-wide significant support for eight loci, including 1q21.1, 2p16.3 (NRXN1), 3q29, 7q11.2, 15q13.3, distal 16p11.2, proximal 16p11.2 and 22q11.2.

(Show Less)