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bioRxiv · 10.1101/040493

A contribution of novel CNVs to schizophrenia from a genome-wide study of 41,321 subjects

Abstract

Genomic copy number variants (CNVs) have been strongly implicated in the etiology of schizophrenia (SCZ). However, apart from a small number of risk variants, elucidation of the CNV contribution to risk has been difficult due to the rarity of risk alleles, all occurring in less than 1% of cases. We sought to address this obstacle through a collaborative effort in which we applied a centralized analysis pipeline to a SCZ cohort of 21,094 cases and 20,227 controls. We observed a global enrichment of CNV burden in cases (OR=1.11, P=5.7e-15), which persisted 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-5). We identified 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. We find support at a suggestive level for nine additional candidate susceptibility and protective loci, which consist predominantly of CNVs mediated by non-allelic homologous recombination (NAHR).

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Christian Marshall, Daniel Howrigan, Daniele Merico, Bhooma Thiruvahindrapuram, Wenting Wu, Douglas Greer, Daniel Antaki, Aniket Shetty, Peter Holmans, Dalila Pinto, Madhusudan Gujral, William Brandler, Dheeraj Malholtra, Zhouzhi Wang, Karin Fuentes Fajarado, Stephan Ripke, Ingrid Agartz, Esben Agerbo, Margot Albus, Madeline Alexander, Farooq Amin, Joshua Atkins, Silviu Bacanu, Richard Belliveau, Sarah Bergen, Marcelo Bertalan, Elizabeth Bevilacqua, Tim Bigdeli, Donald Black, Richard Bruggeman, Nancy Buccola, Randy Buckner, Brendan Bulik-Sullivan, William Byerley, Wiepke Cahn, Guiqing Cai, Murray Cairns, Dominique Campion, Rita Ca. 2016-02-23. A contribution of novel CNVs to schizophrenia from a genome-wide study of 41,321 subjects. https://doi.org/10.1101/040493

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