So many things typically distinguish accomplished athletes from the rest of us—greater strength and endurance, better balance, faster reactions—but one of the more surprising differences is that, according to dental studies, they also tend to get more cavities.

This intriguing phenomenon was the subject of a capstone course in microbiology this past spring, offering undergrads a chance to be part of a burgeoning worldwide scientific effort while using cutting-edge technology.

There are trillions of microbes in the human body; the community of microbes that lives in each of us is our microbiome. As more and more research focuses on microbiomes, it’s becoming clear they play a significant role in human health and wellness. Microbiology 551 students worked to add to that body of research using a next-generation DNA sequencer manufactured by the California-based company Illumina.

“It’s only our department and maybe one or two in California that are doing hands-on work with undergraduates in teaching this technique,” says co-instructor Melissa Christopherson. Christopherson teaches the course with Tim Paustian, both faculty associates in the Department of Bacteriology. “Having students conduct meaningful research with these modern techniques makes them more competitive in the job market and better able to navigate the field of microbiology.”

Students were tasked with comparing the oral microbiomes of athletes and nonathletes, using saliva samples. They sampled a range of students, from UW athletes to occasional exercisers to students who hadn’t exercised for at least five weeks. Once students collected and prepared the samples—including their own oral microbiomes—they sequenced the DNA and determined which microbes were present in each sample.

With so many samples, the students were able to look beyond the question of exercise to test other hypotheses they developed themselves.

“We wound up taking the same data set and asking other questions,” explains Samantha Gieger, who graduated in May with a BS in microbiology and genetics. “In groups of four or five, we looked at the effects of dairy, caffeine or using an electric toothbrush.”

Students presented their projects at a poster session last semester, and their work is currently being analyzed for publication. Their findings will become part of the growing research into microbiomes. Student Sophie Carr BS’16 and Christopherson were invited to the White House last spring for a summit announcing the launch of the National Microbiome Initiative.

As a capstone class, the course offered a research experience requiring students to integrate diverse bodies of knowledge to solve a problem. And it quickly proved invaluable as students considered next steps in their careers.

“I’ve learned so much—how to go about research, what to do when encountering a problem. Troubleshooting is such an important technique,” says Isaiah Rozich BS’16, then a senior majoring in microbiology and Spanish. “Figuring out which solution is best takes a lot of time, and it opened my eyes to what life as a researcher will be like. While it’s overwhelming, I think the end result is gratifying.”