title: ROBO1 polymorphisms, callosal connectivity, and reading skills.
abstract: The genetic effects on specific behavioral phenotypes are putatively mediated by specific neural functions. It remains unexplored how the axon-guidance-receptor gene ROBO1 influences reading performance through the neural system despite the identification of ROBO1 as a susceptibility gene for dyslexia. To address this issue, the present study recruited a group of children with a wide range of reading abilities. Two previously identified reading-related ROBO1 polymorphisms were genotyped, and diffusion and structural MRI were acquired to measure the fiber microstructure of the corpus callosum (CC), the major white-matter tract that connects inter-hemispheric cortical regions. The results confirmed the significant influence of the ROBO1 polymorphisms on reading scores. The fiber microstructures of the midline-CC segments around the genu and splenium were also affected by the ROBO1 polymorphisms. Moreover, a mediation analysis further revealed that the genu could significantly mediate the effects of the ROBO1 polymorphisms on word-list reading performance, which suggests a ROBO1-to-genu-to-reading pathway. The genu-linked cortical morphology, however, was not associated with either the ROBO1 polymorphisms or reading performance. These findings offer direct evidence supporting ROBO1-callosum association in humans and also provide valuable insight into the functions of ROBO1 and the gene-to-brain mechanisms that underlie human reading. Hum Brain Mapp 38:2616-2626, 2017. © 2017 Wiley Periodicals, Inc.
authors.affiliation: State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China.
authors.forename: Xiaochen
authors.initials: X
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Song
authors.affiliation: State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China.
authors.forename: Xinyu
authors.initials: X
authors.lastname: Liang
authors.affiliation: State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China.
authors.forename: Yachao
authors.initials: Y
authors.lastname: Xie
authors.affiliation: State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China.
authors.forename: Chenxi
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Department of Psychology, Chengdu Medical College, Chengdu, 610550, China.
authors.forename: Yuping
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Shu
authors.affiliation: State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China.
authors.forename: Gaolang
authors.identifier: 0000-0001-5788-022X
authors.initials: G
authors.lastname: Gong
mesh_terms: D000293:Adolescent; D002648:Child; D003337:Corpus Callosum / Q000000981:diagnostic imaging* / Q000502:physiology*; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D007839:Functional Laterality / Q000235:genetics; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008954:Models, Biological; D009419:Nerve Tissue Proteins / Q000235:genetics*; D009434:Neural Pathways / Q000000981:diagnostic imaging / Q000502:physiology*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011932:Reading; D011971:Receptors, Immunologic / Q000235:genetics*; D000097905:Roundabout Proteins
chemical_list: D009419:Nerve Tissue Proteins; D011971:Receptors, Immunologic; D000097905:Roundabout Proteins
keywords: ROBO1; corpus callosum; diffusion MRI; mediator; reading