Comprehensive study of the SARS virus, key mutations, and host shifts over space and time
Friday 02/22/2008
Dan Janies and his research team at BMI have been covered in one of the latest stories published by OSU Research News as well as several international newspapers and wire services. At the center of the story is their study of the evolutionary history of the SARS virus. The study includes an interactive google earth map that depicts the spread of the virus, key mutations, and host shifts over space and time.
A key component of the study is that the BMI researchers used whole genomes from within and outside of the SARS cases to create phylogenetic trees. The researchers found that under a wide variety of computational conditions, the SARS viruses isolated from civet cats are not candidates for the original source of SARS virus that lead to the outbreak in humans. From an evolutionary perspective, the SARS viruses isolated from bats are the viruses most closely related to the original source of the SARS in humans. However
from a biochemical perspective, surface proteins on the SARS viruses isolated
from bats do not interact well with the receptors on human cells. Thus there seems to be a missing link, a yet to be discoved virus, between SARS isolated from bats and SARS in humans.
Thus continued surveys of viruses harbored by bats and other creatures is
important to better understand the zoonotic events that lead to the SARS
outbreak.
SARS is an interesting disease because unlike avian influenza it managed to
invade human population worldwide in a matter of months. The current strains
of avian influenza (H5N1) that are the subject of recent concern have taken
over a decade to spread to human populations west of Asia.
Here is a screen shot of the interactive map depicting the spread of SARS over various hosts and geography:
http://supramap.osu.edu/cov/screenshot.jpg
Citation
Janies, D., Habib, F., Alexandrov, B., Hill, A., Pol, D. 2008. Evolution of genomes and host shifts among SARS associated and related coronaviruses. Cladistics. 23.
http://www.blackwell-synergy.com/doi/abs/10.1111/j.1096-0031.2008.00199.x
