Finally, we show that different populations confer different advantages in the discovery of gene-disrupting PTVs, providing guidance for the identification of human “knockouts” to understand gene function. Sampling multiple populations would likely be a fruitful strategy for a researcher investigating common PTV variation. However, discovery of homozygous PTVs is markedly enhanced in the South Asian samples, which come primarily from a Pakistani cohort with 38.3% of individuals self-reporting as having closely related parents, emphasizing the extreme value of consanguineous cohorts for “human knockout” discovery33–35 (Figure 5d). Other approaches to enriching for homozygosity of rare PTVs, such as focusing on bottlenecked populations, have already proved fruitful32,33.