MPRA design Library design To generate the catalogue of fixed human-derived substitutions we used genotyping data from 139 non-human great apes15,68,69,70,71 (10 bonobos, 59 chimpanzees, 43 gorillas and 27 orangutans), all mapped to the human reference genome GRCh37. To restrict the analysis to high-confidence genotypes, we excluded variants that did not meet any of the