A new study conducted by researchers may help explain how and where the virus behind about half of all cold infections evolve in the rhinovirus genome, and what this means for possible vaccines.
"There are a lot of different approaches to treating the cold, none of which seem to be effective. This is partly because we haven't spent a lot of time studying the virus and its history to see how it's responding to the human immune system and drugs," said Keith Crandall, professor of biology and co-author of the study in Brigham Young University.
For their research, the researchers studied genomic sequences available online, and used computer algorithms to estimate how the rhinovirus is related to other viruses.
Nicole Lewis-Rogers, a postdoctoral fellow in the Biology Department and lead author on the study, points out that the rhinovirus is similar to the polio virus, whose vaccine was announced in 1955.
However, according to the researcher, while the polio virus has just three subspecies, the rhinovirus has more than 100 subspecies that continually evolve.
"These viruses could be under the same constraints and yet change differently. That's why it is so hard to create a vaccine," Lewis-Rogers said.
The research team have revealed that the computer program they have developed has helped them identify the parts of the virus genome that enable resistance to drugs and the human immune system.
The immune system does a good job of recognizing viral contaminants and getting rid of them, but the rhinovirus has responded to such defenses by changing its genome so that it is not so easily recognized.
"The virus is evolving solutions against the immune system and drugs. The more we can learn about how the virus evolves solutions, the better we can rid the body of these infections," Crandall said.
The researchers say that it may be helpful for virologists to understand where change occurs in the virus genome, as they can then use the knowledge in designing drugs that target the rhinovirus.
"If you've got 10,000 bits of information, this narrows it down to a handful. Here is where you can start looking," Lewis-Rogers said.
Lewis-Rogers and Crandall hope that their findings may one day lead to the development of better drugs to combat the virus in the most effective way.
Their study has been published in the academic journal Molecular Biology and Evolution.