Fig. 1.

ICCs in ACE model space. Intra-class correlation coefficients (ICC) in a all participants, adjusted for diagnosis and gender, and separately within twin pairs in which both twins were diagnosed with b autism spectrum disorder (ASD) or were c typically-developing (TD) controls, adjusted for gender, were generated within monozygotic (MZ) and dizygotic (DZ) twin pairs and are displayed in relation to ACE model space [a = additive genetics; c = shared family environment; e = unique environment; d = genetic dominance]. Brain structures above or near the CE line are primarily environmentally-mediated whereas brain structures below or near the DE line are primarily genetically-mediated