Presenter: David Aylor
David L. Aylor University of North Carolina
The Collaborative Cross (CC) project is creating hundreds of new inbred laboratory mouse strains. Each new strain descends from eight existing inbred strains, which among them capture an extraordinary amount of genetic diversity and represent three distinct mouse subspecies. Over three-quarters of incipient lines cease to produce offspring during inbreeding. We expect this observation to be explained by epistatic incompatibilities between subspecies, consistent with the Dobzhansky-Muller hypothesis. To assess the genetic basis and mechanism of these incompatibilities, we measured fertility and reproductive parameters in male mice from 358 independent extinct CC lines. Our fertility testing results indicated multiple causes of extinct lines, with male infertility accounting for almost half (46%). We mapped novel loci associated with fertility, sperm count variation, variation in testis weight, and sperm quality.