title: DCDC2 polymorphism is associated with left temporoparietal gray and white matter structures during development.
abstract: Three genes, DYX1C1, DCDC2, and KIAA0319, have been previously associated with dyslexia, neuronal migration, and ciliary function. Three polymorphisms within these genes, rs3743204 (DYX1C1), rs793842 (DCDC2), and rs6935076 (KIAA0319) have also been linked to normal variability of left temporoparietal white matter volume connecting the middle temporal cortex to the angular and supramarginal gyri. Here, we assessed whether these polymorphisms are also related to the cortical thickness of the associated regions during childhood development using a longitudinal dataset of 76 randomly selected children and young adults who were scanned up to three times each, 2 years apart. rs793842 in DCDC2 was significantly associated with the thickness of left angular and supramarginal gyri as well as the left lateral occipital cortex. The cortex was significantly thicker for T-allele carriers, who also had lower white matter volume and lower reading comprehension scores. There was a negative correlation between white matter volume and cortical thickness, but only white matter volume predicted reading comprehension 2 years after scanning. These results show how normal variability in reading comprehension is related to gene, white matter volume, and cortical thickness in the inferior parietal lobe. Possibly, the variability of gray and white matter structures could both be related to the role of DCDC2 in ciliary function, which affects both neuronal migration and axonal outgrowth.
authors.affiliation: Department of Neuroscience, Karolinska Institutet, 171 77 Solna, Sweden.
authors.forename: Fahimeh
authors.initials: F
authors.lastname: Darki
authors.affiliation: Department of Biosciences and Nutrition, Karolinska Institutet, 141 83 Huddinge, Sweden.
authors.forename: Myriam
authors.initials: M
authors.lastname: Peyrard-Janvid
authors.affiliation: Department of Biosciences and Nutrition, Karolinska Institutet, 141 83 Huddinge, Sweden.
authors.forename: Hans
authors.initials: H
authors.lastname: Matsson
authors.affiliation: Department of Biosciences and Nutrition, Karolinska Institutet, 141 83 Huddinge, Sweden, Science for Life Laboratory, Karolinska Institutet, 171 77 Solna, Sweden, and Research Programs Unit, Haartman Institute, University of Helsinki, and Folkhälsan Institute of Genetics, 00014 Helsinki, Finland.
authors.forename: Juha
authors.initials: J
authors.lastname: Kere
authors.affiliation: Department of Neuroscience, Karolinska Institutet, 171 77 Solna, Sweden, torkel.klingberg@ki.se.
authors.forename: Torkel
authors.initials: T
authors.lastname: Klingberg
mesh_terms: D000293:Adolescent; D041923:Adolescent Development / Q000502:physiology*; D000328:Adult; D002648:Child; D002657:Child Development / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008869:Microtubule-Associated Proteins / Q000235:genetics*; D010296:Parietal Lobe / Q000254:growth & development*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D013702:Temporal Lobe / Q000254:growth & development*; D066127:White Matter / Q000254:growth & development*; D055815:Young Adult
chemical_list: C510451:DCDC2 protein, human; D008869:Microtubule-Associated Proteins
keywords: SNP; ciliary function; developmental dyslexia; neuroimaging; reading ability; single nucleotide polymorphism; supramarginal and angular gyrus