A University of Iowa biologist has won a grant of more than $1 million from the National Science Foundation to study how species’ reproductive modes may affect their DNA mutation rates. 

DNA mutation is a fundamental driver for evolution, helping usher in new species and allowing organisms to adapt to changing environments. 

But it also can be dangerous. As new cells are created, they must replicate their entire DNA, which can produce genetic mistakes that can lead to diseases such as cancer. 

Maurine Neiman, professor in the College of Liberal Arts and Sciences and the grant’s recipient, will investigate whether organisms’ reproduction mode affects their DNA mutation rates and, if so, how those differences shape evolution.

She and two graduate students will collect New Zealand freshwater snails that can reproduce sexually or asexually.

After the snails reproduce, Neiman will extract the DNA from the original snails and their offspring, counting DNA differences in the offspring to calculate the mutation rate. 

Neiman will compare the mutation rates between the sexual and asexual snails. 

Meanwhile, study partners at the University of Houston and the University of Toronto, through additional funding from the National Science Foundation, will investigate DNA mutation rates in ciliates — single-celled organisms that can reproduce by themselves or sexually — and in plants that either self-fertilize or reproduce with other plants. 

Combined, the comparisons with the snails, ciliates, and plants could yield clues about how different reproductive modes influence mutation rates within and across species. 

Neiman says the research could improve scientists’ understanding of a wide range of issues, including how DNA mutation could spark cancer, why asexual invasive species can adapt rapidly to new surroundings, and how quickly species may evolve in response to climate change. The findings also could offer insights into aging, which occurs partly due to mutations building up in cells over time.

“This kind of work hasn’t been done before,” Neiman says. “So, it should be broadly intriguing to a lot of people who are interested in the fundamentals of evolution but also with these downstream human problems from cancer to conservation.”

The award will fund her research for four years.