Sarah E. Zanders
Selfish Genes in Gametogenesis
Human society contains both ‘good guys’ (e.g. scientists) who broadly make positive contributions and "bad guys" (e.g. thieves) who make negative contributions. Even if we tend to interact with mostly good guys, our everyday lives are nevertheless shaped by the bad guys: we lock our houses, store our money in banks, and password protect our computers. An outsider studying human behavior could never understand the motives for such behaviors without knowledge of the existence of bad guys and the tactics they employ.
Analogously, genomes also contain ‘good genes’ that promote the health of an organism and "bad genes" that promote their own survival at the expense of their host. Just as bad guys shape our daily lives, parasitic bad genes can affect crucial cellular processes. This is especially true of gametogenesis, the process that generates eggs and sperm. In gametogenesis, bad genes often cheat the process to ensure their transmission into the next generation. As bad genes are ubiquitous, we can never fully understand gametogenesis and the origins of infertility without identifying the bad genes and learning about the tactics they employ.
Meiotic drivers are one type of bad gene. These DNA parasites exploit gametogenesis to bias their own transmission. Instead of being transmitted to 50% of gametes (e.g. sperm) like regular alleles, meiotic drive alleles can be transmitted into up to 100% of functional gametes. We are studying the wtf family of meiotic drive genes in the fission yeast, Schizosaccharomyces pombe. We aim to uncover the strategies used by wtf genes and explore how they have affected genome evolution. We hope our studies will uncover general themes about meiotic drivers that could be used to guide analyses of other natural drivers, in addition to artificial gene drives which are engineered to control natural populations, such as mosquitos.