Whole exome sequencing of wild-derived inbred strains of mice improves power to link phenotype and genotype

The house mouseis a powerful model to dissect the geneticbasis of phenotypic variation, and serves as a model to study human diseases. Despite a wealth of discoveries, most classical laboratory strains have captured only a small fraction of genetic variationknown to segregate in their wild progenitors, and existing strains are often related to each other in complex ways. Inbred strains of mice independently derived from natural populations have the potential to increase power in geneticstudies with the addition of novel genetic variation. Here, we perform exome-enrichment and high-throughput sequencing (~8× coverage) of 26 wild-derived strains known in the mouse research community as the “Montpellier strains.” We identified 1.46 million SNPs in our dataset, approximately 19% of which have not been detected from other inbred strains. This novel genetic variationis expected to contribute to phenotypic variation, as they include 18,496 nonsynonymous variants and 262 early stopcodons. Simulations demonstrate that the higher density of genetic variationin the Montpellier strains provides increased power for quantitative geneticstudies. Inasmuch as the power to connect genotype to phenotype depends on genetic variation, it is important to incorporate these additional geneticstrains into future research programs.