Scientists have for the first time sequenced an ancient RNA genome – of a barley virus once believed to be only 150 years old – pushing its origin back at least 2,000 years and revealing how intense farming at the time of the Crusades contributed to its spread.
This is a good report about a VERY interesting finding – with one flaw. They go on, apparently, about how BSMV is a "new virus": why would anyone think that? Since the late 1980s, Adrian Gibbs and others have pointed out that tobamoviruses are probably ancient; just because RNA CAN evolve fast doesn’t mean it does, in terms of encoding functional elements. Gibbs showed this for plant viruses; it has also been done for the HIV/SIV complex, where it is shown that a similar divergence in sequence among theses viruses to all animals since the Cretaceous, has led to NO changes in morphology, or gene function.
The simple fact is that having "plastic" genome in comparison to eukaryotic cells does NOT mean that ssRNA viruses may not be ancient.
Having said all that, it really is a tour de force to have sequenced a virus that old – aided by the fact, I am sure, that BSMV is hardy little beast, with a really stable vision.
Now, to find those hundred-year-old maize leaves put away with maize streak virus symptoms….B-)
Thanks to @Elsevier Microbiol* for pointing this out!
See on www.sciencedaily.com