Scientists Uncode Genes for the Common Cold

What would the world be like if scientists could cure the common cold? Fewer people would miss work, school or their favorite activities. Productivity would increase, and people's noses would be a lot happier.

But the common cold has thus far eluded a cure - in part because there's not a single cause for the common cold. Colds can be brought on by more than 100 different viruses.

Dr. Stephen Liggett from the University of Maryland says he was surprised that scientists had decoded the genes for only a few of them.

"I was struck by the fact that while there were over 100 known serotypes, also called strains... only eight of them had ever had their complete genomes sequenced," he says.

Liggett worked with a team of geneticists to decipher all of those 100-plus cold strains. They are part of the same family of viruses - called rhinoviruses - but they cause different symptoms. Some groups may give a person an inner-ear infection, for example. Others are more likely to cause asthma-like symptoms.

"It became clear to us that there are these groups, and that maybe there was not going to be a one-drug-fits-all approach to treating rhinovirus infections, but maybe four or five," Liggett says.

"Which is still quite acceptable, because we've essentially been unsuccessful so far," he adds.

Rhinoviruses are known to mutate into new forms. Liggett says that in the course of unraveling how rhinoviruses evolve, he learned more about how those mutations occur.

"They can recombine... two rhinoviruses, if you are co-infected, can recombine to make a third," he says. "That was not predicted by anyone."

But despite the fact that rhinoviruses are wily, Liggett believes that knowing their genetic sequence is key to developing cures for the common cold.

"You know, I have very strong optimism for that and, you know, people might laugh, but I've got the whole genetic code for every one of these viruses... that's got to give me an advantage in trying to do that," he adds with a laugh.

Liggett says the next step is to look for other rhinoviruses that may have escaped him the first time around and see how different strains affect different people. He says eventually drug makers can find ways to exploit this new information to bring relief to millions of noses.

His research is published in the journal Science.