The developmental stages include post-conceptual week (PCW) 8–10, PCW 8–12, PCW 13, PCW 16, PCW 17–22 and postnatal 4 months, 10 months and 12 months. The mean expression level together with the standard error of the mean (SEM) was plotted across the developmental stages for genes affected by de novo mutations identified in the PTB (panel a), term (panel b) and GoNL (panel c) cohorts. The same analysis was also performed on the entire transcriptome in each temporal epoch (panel d, the SEM is too small to be shown due to large sample size, i.e. overall 20,000 genes included). Gene expression values were normalized across different developmental stages.