Only significant enrichment in the set of 18 genes identified based on credible variants was found. We therefore looked specifically into these genes to identify whether the signal was driven by specific genes. rPTVs were found in 13 of the genes, and eight of these genes had more rPTVs in cases than controls when looking at raw counts (Supplementary Table 16). We performed gene-based burden test using EPACTS (https://genome.sph.umich.edu/wiki/EPACTS) and a logistic Wald test (correcting using the covariates as described above). Additionally, in order to increase power to detect an increased burden of rPTVs at the gene level in ADHD cases, we combined iPSYCH controls with information about rPTVs in gnomAD (non-Finnish European individuals), done as described previously17. We performed these gene-based tests using Fisher’s exact test, and only the following genes were considered: (1) genes with a higher number rSYN in gnomAD controls compared to iPSYCH cases, and (2) genes with a higher rate of rPTVs in cases compared to controls in the iPSYCH data.
