RT Journal Article SR Electronic T1 A Comprehensive Quantitative Genetic Analysis of Cerebral Surface Area in Youth JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 3028 OP 3040 DO 10.1523/JNEUROSCI.2248-18.2019 VO 39 IS 16 A1 Schmitt, J. Eric A1 Neale, Michael C. A1 Clasen, Liv S. A1 Liu, Siyuan A1 Seidlitz, Jakob A1 Pritikin, Joshua N. A1 Chu, Alan A1 Wallace, Gregory L. A1 Lee, Nancy Raitano A1 Giedd, Jay N. A1 Raznahan, Armin YR 2019 UL http://www.jneurosci.org/content/39/16/3028.abstract AB The genetics of cortical arealization in youth is not well understood. In this study, we use a genetically informative sample of 677 typically developing children and adolescents (mean age 12.72 years), high-resolution MRI, and quantitative genetic methodology to address several fundamental questions on the genetics of cerebral surface area. We estimate that >85% of the phenotypic variance in total brain surface area in youth is attributable to additive genetic factors. We also observed pronounced regional variability in the genetic influences on surface area, with the most heritable areas seen in primary visual and visual association cortex. A shared global genetic factor strongly influenced large areas of the frontal and temporal cortex, mirroring regions that are the most evolutionarily novel in humans relative to other primates. In contrast to studies on older populations, we observed statistically significant genetic correlations between measures of surface area and cortical thickness (rG = 0.63), suggestive of overlapping genetic influences between these endophenotypes early in life. Finally, we identified strong and highly asymmetric genetically mediated associations between Full-Scale Intelligence Quotient and left perisylvian surface area, particularly receptive language centers. Our findings suggest that spatially complex and temporally dynamic genetic factors are influencing cerebral surface area in our species.SIGNIFICANCE STATEMENT Over evolution, the human cortex has undergone massive expansion. In humans, patterns of neurodevelopmental expansion mirror evolutionary changes. However, there is a sparsity of information on how genetics impacts surface area maturation. Here, we present a systematic analysis of the genetics of cerebral surface area in youth. We confirm prior research that implicates genetics as the dominant force influencing individual differences in global surface area. We also find evidence that evolutionarily novel brain regions share common genetics, that overlapping genetic factors influence both area and thickness in youth, and the presence of strong genetically mediated associations between intelligence and surface area in language centers. These findings further elucidate the complex role that genetics plays in brain development and function.