These data highlight specific AD risk genes that exhibit little variance with most contributions from a specific founder strain (ie, Ace, Wnt3, Mapt, Grn) as well as AD risk genes that exhibit a high level of variance in founder strain contribution (ie, Cass4, Rbck1, Mme, Celf1, Spi1, Slc24a4) (Figure 6C). This evidence concerns the gene CASS4 and Alzheimer disease.