Effects of copy number variations on brain structure and risk for psychiatric illness: Large‐scale studies from theENIGMAworking groups onCNVs
Authors: Sønderby Ida E. , Ching Christopher R. K. , Thomopoulos Sophia I. , van der Meer Dennis , Sun Daqiang , Villalon‐Reina Julio E. , Agartz Ingrid , Amunts Katrin , Arango Celso , Armstrong Nicola J. , Ayesa‐Arriola Rosa , Bakker Geor , Bassett Anne S. , Boomsma Dorret I. , Bülow Robin , Butcher Nancy J. , Calhoun Vince D. , Caspers Svenja , Chow Eva W. C. , Cichon Sven , Ciufolini Simone , Craig Michael C. , Crespo‐Facorro Benedicto , Cunningham Adam C. , Dale Anders M. , Dazzan Paola , de Zubicaray Greig I. , Djurovic Srdjan , Doherty Joanne L. , Donohoe Gary , Draganski Bogdan , Durdle Courtney A. , Ehrlich Stefan , Emanuel Beverly S. , Espeseth Thomas , Fisher Simon E. , Ge Tian , Glahn David C. , Grabe Hans J. , Gur Raquel E. , Gutman Boris A. , Haavik Jan , Håberg Asta K. , Hansen Laura A. , Hashimoto Ryota , Hibar Derrek P. , Holmes Avram J. , Hottenga Jouke‐Jan , Hulshoff Pol Hilleke E. , Jalbrzikowski Maria , Knowles Emma E. M. , Kushan Leila , Linden David E. J. , Liu Jingyu , Lundervold Astri J. , Martin‐Brevet Sandra , Martínez Kenia , Mather Karen A. , Mathias Samuel R. , McDonald‐McGinn Donna M. , McRae Allan F. , Medland Sarah E. , Moberget Torgeir , Modenato Claudia , Monereo Sánchez Jennifer , Moreau Clara A. , Mühleisen Thomas W. , Paus Tomas , Pausova Zdenka , Prieto Carlos , Ragothaman Anjanibhargavi , Reinbold Céline S. , Reis Marques Tiago , Repetto Gabriela M. , Reymond Alexandre , Roalf David R. , Rodriguez‐Herreros Borja , Rucker James J. , Sachdev Perminder S. , Schmitt James E. , Schofield Peter R. , Silva Ana I. , Stefansson Hreinn , Stein Dan J. , Tamnes Christian K. , Tordesillas‐Gutiérrez Diana , Ulfarsson Magnus O. , Vajdi Ariana , van 't Ent Dennis , van den Bree Marianne B. M. , Vassos Evangelos , Vázquez‐Bourgon Javier , Vila‐Rodriguez Fidel , Walters G. Bragi , Wen Wei , Westlye Lars T. , Wittfeld Katharina , Zackai Elaine H. , Stefánsson Kári , Jacquemont Sebastien , Thompson Paul M. , Bearden Carrie E. , Andreassen Ole A. ,   for the ENIGMA‐CNV Working Group,   for the ENIGMA 22q11.2 Deletion Syndrome Working Group
Published: February 2021

The Enhancing NeuroImaging Genetics through Meta‐Analysis copy number variant (ENIGMA‐CNV) and 22q11.2 Deletion Syndrome Working Groups (22q‐ENIGMA WGs) were created to gain insight into the involvement of genetic factors in human brain development and related cognitive, psychiatric and behavioral manifestations. To that end, the ENIGMA‐CNV WG has collated CNV and magnetic resonance imaging (MRI) data from ~49,000 individuals across 38 global research sites, yielding one of the largest studies to date on the effects of CNVs on brain structures in the general population. The 22q‐ENIGMA WG includes 12 international research centers that assessed over 533 individuals with a confirmed 22q11.2 deletion syndrome, 40 with 22q11.2 duplications, and 333 typically developing controls, creating the largest‐ever 22q11.2 CNV neuroimaging data set. In this review, we outline the ENIGMA infrastructure and procedures for multi‐site analysis of CNVs and MRI data. So far, ENIGMA has identified effects of the 22q11.2, 16p11.2 distal, 15q11.2, and 1q21.1 distal CNVs on subcortical and cortical brain structures. Each CNV is associated with differences in cognitive, neurodevelopmental and neuropsychiatric traits, with characteristic patterns of brain structural abnormalities. Evidence of gene‐dosage effects on distinct brain regions also emerged, providing further insight into genotype–phenotype relationships. Taken together, these results offer a more comprehensive picture of molecular mechanisms involved in typical and atypical brain development. This “genotype‐first” approach also contributes to our understanding of the etiopathogenesis of brain disorders. Finally, we outline future directions to better understand effects of CNVs on brain structure and behavior.