PERSPECTIVE R2d2 and Hyperdrive Mechanisms (in Mouse Meiosis)

“Mendelism is a magnificent invention for fairly testing genes in many combinations, like an elegant factorial experimental design. Yet it is vulnerable at many points and is in constant danger of subversion by cheaters that seem particularly adept at finding such points.”- James F. Crow [1] Mendelian transmission is established during meiosis, the cell division that generates haploid gametes (e.g., sperm and eggs) from diploid germ cells. Meiosis does not, however, have to be fair. Selfish genetic elements, or meiotic drivers, have evolved to cheat this process in order to be packaged into functional gametes more often than the expected 50 % probability. By biasing allele transmission in their favor, meiotic drive alleles can short-circuit natural selection, caus-ing their spread even if they are harmful to organismal fitness. Indeed, meiotic drive alleles are thought to be directly or indirectly associated with infertility in diverse eukaryotes, from fungi to flies to humans [2]. Drive occurring in male meiosis may have immediate consequences to fertility, potentially facilitating its detection. In contrast, drive in female meiosis could lead to very subtle skews in inheritance patterns and no overt signs of infertility; such driver alleles may therefore go unnoticed even if they are more pervasive [3, 4]. Surprisingly few meiotic drivers have been conclusively identified. There are three major roadblocks to the efficien