ABSTRACT
Genic constraint describes how tolerant a gene is of nonsynonymous variation before it is removed from the population by negative selection. Here, we provide the first estimates of intraspecific constraint for mouse genes genome-wide, and show constraint is positively correlated between human and mouse orthologues (r = 0.806). We assess the relationships between mouse gene constraint and knockout phenotypes, showing gene constraint is positively associated with pleiotropy (ie an increased number of phenotype associations (R2 = 0.65)), in addition to an enrichment in lethal, developmental, and craniofacial knockout phenotypes amongst the most constrained genes. Finally, we show mouse constraint can be used to predict human genes associated with Mendelian disease, and is positively correlated with an increase in the number of known pathogenic variants in the human orthologue (R2 = 0.23). Our metrics of mouse and human constraint are available to inform future research using mouse models.