BS, Biology, University of Iowa
PhD, Genetics and Development, Cornell University
Sarah Zanders, PhD, fell in love with genetics as an undergrad at the University of Iowa, after taking her first genetics course. She spent many happy hours in the lab there, digging into the genome of budding yeast and making mutations — on purpose. “It was pretty thrilling to see the power of genetics at work,” she remembers. Today, her continued fascination with what’s passed on from one generation to the next drives her lab’s research on genetic parasites, and how they cause infertility.
After graduating with a BS in biology, Zanders moved from one coast to the other as she completed her PhD at Cornell University in Ithaca, New York, and a postdoctoral fellowship at the Fred Hutchison Cancer Research Center in Seattle, Washington. Along the way, she became intrigued by parasitic genes and their role in the evolution of genomes. Zanders has made significant contributions to the field including discovering meiotic drivers in fission yeast. Zanders set up her lab in 2016 at the Stowers Institute, just a stone’s throw away from Iowa, where she got her start.
Apart from research, educating the next generation of scientists is a top priority for Zanders, who credits her mentors for teaching her how to think critically, communicate, and conduct research. “Basically, they just taught me how to do science,” Zanders says. In July 2019, Zanders became the first person to fill the role of Vice Dean of the Graduate School of the Stowers Institute. She aspires to promote diversity and inclusion in the graduate school and in the life sciences. As a mentor and a teacher, she strives to prepare students to conduct innovative and creative investigations of their own. “I want them to become independent scientists. I want them to have confidence in their own abilities,” she says.
The Zanders Lab studies components of the genome that act as parasites and sometimes cause infertility. These components are described as “selfish” because they do nothing to promote the overall fitness of an organism. Instead, their sole purpose is to survive and spread. The lab’s researchers examine how these selfish components wreak havoc on the genome and the organisms they inhabit. Their studies offer insight on genome evolution, speciation (how species become different from one another), and the origins of infertility in organisms, including humans.
In particular, Zanders’ lab is investigating a class of selfish genes, called meiotic drive genes, which can be found in organisms ranging from plants to humans. Meiosis is a process where cells divide and give rise to gametes such as sperm and eggs. During this process, meiotic drive genes appear to seek out and kill their competition – gametes that haven’t inherited the selfish gene. As a result, the meiotic drive genes force their own transmission into gametes, but the organism may experience reduced fertility overall.
It’s this seeming paradox that inspires Zanders’ research. Evolution favors fertile individuals, yet selfish genes that decrease fertility survive and thrive. Why? By studying fission yeast, Zanders and her team are delving deeper into the mechanisms driving selfish genes, identifying more selfish genes, and expanding their research into additional species to find the answer.
Zanders’ accomplishments include the discovery of meiotic drive genes as a postdoctoral researcher. Her research findings, published in 2014 in eLife, suggest that selfish genes play a role in speciation. In collaboration with Fred Hutchinson Cancer Research Center researchers, Zanders and colleagues identified the parasitic selfish gene S. kambucha wtf4, which acts as both a poison and an antidote to eliminate its competition and ensure its transmission into the next generation. The finding, published in 2017 in eLife, expands knowledge of how gamete-killing meiotic drive genes can contribute to infertility. Zanders’ work earned widespread recognition in 2018, as she received three highly competitive scientific awards: the Basil O’Connor Starter Scholar Award from the March of Dimes, the National Institutes of Health (NIH) Director’s New Innovator Award, and the honor of being named a 2018 Searle Scholar.
Looking to the future, Zanders and her lab aim to uncover the strategies used by selfish genes and discover how they have affected genome evolution. It’s an area of research that’s ripe for exploration, she says. “I want to highlight the under-appreciated aspects of genetics and bring those things to life.”