The researchers extracted DNA from tissue samples taken from boas and pythons diagnosed with IBD, and used rapid, high-throughput techniques to learn the sequence of those strands of DNA. In amongst all the snake DNA sequences there were sequences of DNA that clearly belonged to viruses - viruses that are members of the arenavirus family. The authors were later able to grow and isolate one of those viruses using snake tissues cultured in the laboratory.
While it is an important development from a practical standpoint, since identifying the causative agent for a disease is the first step in developing treatments, vaccines, diagnostics, and prevention policies it is also an incredible discovery for virology: the virus belongs to a group of viruses no one knew existed.
"This is one of the most exciting things that has happened to us in virology in a very long time. The fact that we have apparently identified a whole new lineage of arenaviruses that may predate the New and Old world is very exciting," says Buchmeier.
According to Buchmeier, this new isolate doesn't fall neatly into either of the two known categories of arenaviruses, Old World arenaviruses and New World arenaviruses. The fact that the virus was found in snakes adds another surprise twist, since up until now arenaviruses had only ever been found in mammals.
Metagenomic techniques that examine large samples of DNA for small bits of information, like the approach used in the study, are extremely powerful for identifying new viruses, Buchmeier says.
"Twenty years ago we would have called this a fishing expedition. It is fishing, but the techniques are so good and so sensitive that they allow us to determine which new types are there," says Buchmeier.
|Contact: Jim Sliwa|
American Society for Microbiology