Taken to its ultimate outcome, the research that biology professor Dr. Steve Howard is working on could help disarm deadly retroviruses such as HIV or SARS.
Howard, associate professor of biology at Middle Tennessee State University, would be the first to advise against making that kind of quantum-leap claim. It's much too early. But assuming that the research that led to the polio vaccine first crawled, then walked, then charted a new course for civilization itself, Howard's discovery is more than significant.
Co-authored by Drs. J.F. Fontanari and A. Colato of the Universidade de Sao Paulo in Brazil, Howard's study was published recently in the Physical Review Letters, the top international journal in physics.
"I became aware of a paper these two theoretical physicists published, and it turns out they were interested in some of the same questions that I had been interested in," Howard said.
Trained as a population geneticist and evolutionary biologist, Howard had always been intrigued by the process in which organisms become adapted to their environments. He was particularly interested in understanding how the process of evolution affects the relationship between disease-causing organisms and other organisms that are infected by these organisms. Research over the past several years points to a genetic base for these infections.
"There are certain sequences of DNA in these viruses and other disease-causing organisms that enable them to infect humans or other species that have certain sequences of DNA. In other words, there is a lock-and-key mechanism in determining the genetic basis to infections," he explained.
"What we're interested in is understanding the potential for random mutations to accumulate in the genetic material of viruses to the point where there are so many mistakes in the DNA or RNA that they can no longer reproduce or maintain themselves."
Howard said that determining the expected rates at which these mutations could accumulate all distills down to a math problem. It was with this realization that the three researchers linked up and discovered they could make more headway by combining their efforts.
"We used a mathematical approach—known as 'branching process theory'—to generate a theoretical prediction concerning the rate at which random mutations could accumulate in the genetic material of viruses like HIV," Howard continued. "The result we got was extraordinary. What we found was that under certain conditions, the rates that these mistakes can accumulate is actually accelerated by the process of natural selection. This is surprising, as natural selection typically leads to a reduction in the number of mutations. … The implication is that we could accelerate the rate at which these virus populations go extinct."