Effects of copy number variations on brain structure and risk for psychiatric illness: Large‐scale studies from the<scp>ENIGMA</scp>working groups on<scp>CNVs</scp>
Ida E. Sønderby, Christopher R. K. Ching, Sophia I. Thomopoulos, Dennis van der Meer, Daqiang Sun, Julio E. Villalón‐Reina, Ingrid Agartz, Katrin Amunts, Celso Arango, Nicola J. Armstrong, Rosa Ayesa‐Arriola, Geor Bakker, Anne S. Bassett, Dorret I. Boomsma, Robin Bülow, Nancy J. Butcher, Vince D. Calhoun, Svenja Caspers, Eva W.C. Chow, Sven Cichon, Simone Ciufolini, Michael Craig, Benedicto Crespo‐Facorro, Adam Cunningham, Anders M. Dale, Paola Dazzan, Greig I. de Zubicaray, Srdjan Djurovic, Joanne Doherty, Gary Donohoe, Bogdan Draganski, Courtney A. Durdle, Stefan Ehrlich, Beverly S. Emanuel, Thomas Espeseth, Simon E. Fisher, Tian Ge, David C. Glahn, Hans J. Grabe, Raquel E. Gur, Boris A. Gutman, Jan Haavik, Asta K. Håberg, Laura A. Hansen, Ryota Hashimoto, Derrek P. Hibar, Avram J. Holmes, Jouke‐Jan Hottenga, Hilleke E. Hulshoff Pol, Maria Jalbrzikowski, Emma E. M. Knowles, Leila Kushan, David E.J. Linden, Jingyu Liu, Astri J. Lundervold, Sandra Martin‐Brevet, Kenia Martínez, Karen A. Mather, Samuel R. Mathias, Donna M. McDonald‐McGinn, Allan F. McRae, Sarah E. Medland, Torgeir Moberget, Claudia Modenato, Jennifer Monereo Sánchez, Clara Moreau, Thomas W. Mühleisen, Tomáš Paus, Zdenka Pausová, Carlos Alberto Vanegas Prieto, Anjanibhargavi Ragothaman, Céline S. Reinbold, Tiago Reis Marques, Gabriela M. Repetto, Alexandre Reymond, David R. Roalf, Borja Rodríguez‐Herreros, James Rucker, Perminder S. Sachdev, James E. Schmitt, Peter R. Schofield, Ana Isabel Silva, Hreinn Stefánsson, Dan J. Stein, Christian K. Tamnes, Diana Tordesillas‐Gutiérrez, Magnús Ö. Úlfarsson, Ariana Vajdi, Dennis van ‘t Ent, Marianne B. M. van den Bree, Evangelos Vassos, Javier Vázquez-Bourgón, Fidel Vila‐Rodriguez, G. Bragi Walters, Wei Wen, Lars T. Westlye, Katharina Wittfeld, Elaine H. Zackai, Kári Stefánsson, Sébastien Jacquemont
Abstract
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.