title: GENETIC ANALYSIS OF STRUCTURAL BRAIN CONNECTIVITY USING DICCCOL MODELS OF DIFFUSION MRI IN 522 TWINS.
abstract: Genetic and environmental factors affect white matter connectivity in the normal brain, and they also influence diseases in which brain connectivity is altered. Little is known about genetic influences on brain connectivity, despite wide variations in the brain's neural pathways. Here we applied the "DICCCOL" framework to analyze structural connectivity, in 261 twin pairs (522 participants, mean age: 21.8 y ± 2.7SD). We encoded connectivity patterns by projecting the white matter (WM) bundles of all "DICCCOLs" as a tracemap (TM). Next we fitted an A/C/E structural equation model to estimate additive genetic (A), common environmental (C), and unique environmental/error (E) components of the observed variations in brain connectivity. We found 44 "heritable DICCCOLs" whose connectivity was genetically influenced (a2>1%); half of them showed significant heritability (a2>20%). Our analysis of genetic influences on WM structural connectivity suggests high heritability for some WM projection patterns, yielding new targets for genome-wide association studies.
authors.affiliation: Imaging Genetics Center, University of Southern California, CA, USA.
authors.forename: Dajiang
authors.initials: D
authors.lastname: Zhu
authors.affiliation: Imaging Genetics Center, University of Southern California, CA, USA.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhan
authors.affiliation: Imaging Genetics Center, University of Southern California, CA, USA.
authors.forename: Joshua
authors.initials: J
authors.lastname: Faskowitz
authors.affiliation: Imaging Genetics Center, University of Southern California, CA, USA.
authors.forename: Madelaine
authors.initials: M
authors.lastname: Daianu
authors.affiliation: Imaging Genetics Center, University of Southern California, CA, USA.
authors.forename: Neda
authors.initials: N
authors.lastname: Jahanshad
authors.affiliation: School of Psychology, University of Queensland, Brisbane, Australia.
authors.forename: Greig I
authors.initials: GI
authors.lastname: de Zubicaray
authors.affiliation: Center for Advanced Imaging, University of Queensland, Brisbane, Australia.
authors.forename: Katie L
authors.initials: KL
authors.lastname: McMahon
authors.affiliation: QIMR Berghofer Medical Research Institute, Brisbane, Australia.
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Martin
authors.affiliation: QIMR Berghofer Medical Research Institute, Brisbane, Australia.
authors.forename: Margaret J
authors.initials: MJ
authors.lastname: Wright
authors.affiliation: Imaging Genetics Center, University of Southern California, CA, USA.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Thompson
keywords: DICCCOL; heritability