Eight founder inbred strains (129S1/SvImJ, A/J, C57BL/6J, NOD/ShiLtJ, NZO/HlLtJ, CAST/EiJ, PWK/PhJ, and WSB/EiJ) were used to generate F1 mice which were then distributed to three breeding sites, Oak Ridge National Laboratory (OR); Western Australian Institute for Medical Research/Geniad Ltd. (AU), and International Livestock Research Institute, Kenya (IL). The U.S. population has since moved to the University of North Carolina (UNC) and the Kenyan population to Tel Aviv University (TAU). To generate the set, three generations of matings were performed to incorporate genomic contributions from each of the founder strains (‘funnel breedings’) followed by extensive inbreeding. A subset of the IL and AU lines were imported into the Systems genetics Core Facility (SGCF) at UNC where they were inbred until the strains were ready for distribution. A portion of the strains at the SGCF at UNC including lines originating from OR, IL and AU were imported to The Jackson Laboratory and are maintained via sibling mating.