A team of researchers has published the genome sequences of the 100 most common cold viruses. As Nature reports, the work could help develop new therapies or figure out why some rhinovirus strains cause stronger symptoms than others.
Think the cold virus is harmless? Think again, Nature says. Colds purportedly cost the United States about $60 billion a year, and in children, the sniffles "can cause middle-ear infections or increase the likelihood of developing asthma." HRV-C, a freshly discovered class of cold viruses, can even bring on serious lung infections.
All this havoc is caused by a tiny virus only about 30 nanometres in diameter, with a genome that is a mere 7,000 bases long — a minute speck compared with the human genome, which has more than three billion bases. Although the genomes of a few strains of cold virus had been sequenced, no one had compiled the full sequences of the 99 strains frequently studied by researchers. These have been collected from patients over decades and form a reference library.
[Stephen Liggett, director of cardiopulmonary genomics at the University of Maryland Medical Center in Baltimore], [Ann Palmenberg, a virologist at the University of Wisconsin, Madison] and their colleagues decided to fill this gap by sequencing the reference-library strains, along with 10 additional viruses isolated from patients with upper respiratory infections. They compared these sequences and the previously reported HRV-C genomes with one another to look for patterns and evolutionary relationships (see human rhinovirus genome tree . . . ).
Ligett and his team have reportedly begun sequencing even more strains. Nature says the researchers could figure out which strains are dominant in which parts of the world, and they may also find out "the viral characteristics that are associated with longer, more symptomatic infections."