The Howard Hughes Medical Institute announced on Tuesday that it would donate more than $600 million over the next five years to 56 of the nation's top scientists to give them a chance to answer some of the world's most difficult medical research questions.

Two University professors - Mercedes Pascual, an associate professor of ecology and evolutionary biology, and John Moran, an associate professor of human genetics and internal medicine - were chosen as Hughes grant recipients from a pool of more than 1,000 applicants.

The Hughes grant is unique not only because it's a huge financial undertaking, but also because it's designed to fund research endeavors that are less conventional and potentially groundbreaking.

Though this game of scientific discovery doesn't offer any guarantees, Pascual said taking a chance is a vital part of the research process.

"All important research has to be risky," Pascual said. "Otherwise, you're doing something that is probably just more of the same."

And more of the same isn't what Pascual has in store for the next five years. With her grant, she'll continue to study the relationship between climate and the spread of infectious diseases like cholera and malaria.

Her work, which focuses mostly on populations in India, Bangladesh and Africa, attempts to predict future disease outbreaks and epidemics by studying the short-term impact of seasonal weather cycles and the long-term impact of issues like global warming.

For the spread of cholera in Bangladesh, for example Pascual looked at the role of warmer sea surface temperatures in the Pacific Ocean during El Nino years. She was quick to point out, however, that a correlation between climate and disease was just one part of a complicated equation that could help predict future epidemics.

"Simple correlations between climate and disease often do not work," Pascual said. "Even in the absence of climate, disease dynamics can actually have very complicated temporal patterns because of processes such as population immunity and transmission."

Pascual said the real challenge was to disentangle the effect of climate change from the natural processes that have to do only with the disease itself.

For the past 10 years, Pascual has relied mostly on historical data to try to uncover a connection between climate and disease. With the new grant, Pascual said she could begin conducting more field research to help predict environmentally driven outbreaks.

Moran's research has a similar element of uncertainty and the potential to make an equally large impact, but takes place on a much smaller scale.

He studies what is known as "long interspersed element-1," which comprises about 17 percent of the human genome.

These elements, some of which have the ability to move and jump, can cause mutations in the human genome. They have been linked to genetic disorders including hemophilia and muscular dystrophy.

Though Moran said no one is quite sure about the true purpose of these elements, he hopes to uncover some of the mystery behind how, why and when these pieces jump to different areas of the human genome with his newly awarded grant.

After the human genome draft sequence was completed in 2001, Moran said that researchers deemed a large part of the human genome to be "junk." But Moran said through his work, he hopes to understand a part of the genetic sequence that has been previously discarded and ignored.

"What I really hope to do is dig a deeper trench into the basic science of how transposable elements have impacted the human genome," Moran said. "And from that we'll understand more human biology and we'll start to understand the components of the genome that people have largely dismissed."

Though neither scientist said they could be sure of the outcome of their research, both have five years to accomplish a landmark scientific achievement.