Longitudinal imaging and quantitative genetic studies have both provided important insights into the nature of human brain development. In the present study we combine these modalities to obtain dynamic anatomical maps of the genetic contributions to cortical thickness through childhood and adolescence. A total of 1,748 anatomic MRI scans from 792 healthy twins and siblings were studied with up to eight time points per subject. Using genetically informative latent growth curve modeling of 81,924 measures of cortical thickness, changes in the genetic contributions to cortical development could be visualized across the age range at high resolution. There was highly statistically significant (P < 0.0001) genetic variance throughout the majority of the cerebral cortex, with the regions of highest heritability including the most evolutionarily novel regions of the brain. Dynamic modeling of changes in heritability over time demonstrated that the heritability of cortical thickness increases gradually throughout late childhood and adolescence, with sequential emergence of three large regions of high heritability in the temporal poles, the inferior parietal lobes, and the superior and dorsolateral frontal cortices.

Twin and Family Longitudinal Measures of Cortical Thickness.RData file containing demographic information and vertex-level longitudinal measures of cortical thickness. Users will need to install the free software package R at http://http://cran.us.r-project.org. The readme object within the .RData file contains descriptions of individual variables. Vectors of vertex-level results can be visualized using brain-view2; see https://wiki.mouseimaging.ca/display/MICePub/brain-view to access information on how to download brainview. Further details on cortical thickness measures and zygosity determination can be found in the original manuscript.DynamicHeritability2.RData