First Peer-reviewed SARS Genome Sequence Appears in Science

All Information Now Freely Available Through Science / AAAS

The first peer-reviewed studies of the genomic sequences of two SARS virus strains are being released today by the journal Science, published by the American Association for the Advancement of Science (AAAS).

The studies confirm that the virus is a new variety of coronavirus, and provide a first look at the molecular components of the virus. The information should help speed efforts to diagnose, treat, and prevent the global epidemic of severe acute respiratory syndrome, or SARS.

"Both research teams produced these genomic sequences quickly and efficiently, in a model of cooperation among various groups. Because this information is crucial to the public health, Science is making it immediately available following an important and promptly conducted peer review," said Don Kennedy, Science's Editor-in-Chief.

"The genomic sequence of the virus can lead researchers to the tools they need for fighting this new disease. From here, researchers should be able to target these proteins in diagnostic tests, therapies, or possibly a vaccine for SARS," said Katrina Kelner, Deputy Editor, Life Sciences, at Science.

A Canadian team was the first to sequence the genome of a SARS viral strain, taken from a patient in Toronto. Shortly thereafter, a U.S.-based team sequenced the so-called Urbani strain, which Dutch researchers had linked directly to lung disease. Both teams have posted their sequences on the Internet. The sequences are quite similar, with a small difference in length.

Both the teams have identified the pieces of the genome that should contain instructions for producing proteins. This includes putative genes for four essential proteins that enable this type of virus, called a coronavirus, to enter host cells and replicate. The researchers also identified five regions coding for "non-essential" proteins, which may nonetheless help shed light on the virus' origins.

Known coronaviruses cause mild upper-respiratory illness in humans, in some cases, and a variety of diseases in other animals.

While the SARS genome has the same overall structure as those of the three known classes of coronavirus, the researchers found key differences when they looked at the predicted amino acid structures of the individual proteins. By statistically analyzing the differences among the proteins, both teams concluded that the SARS virus is a novel class of coronavirus, rather than a recent mutant of a known variety.

These findings set the stage for further investigations into the viral proteins' functions, possibly uncovering new targets for therapies or vaccines.

Research teams in Singapore and Beijing have also sequenced strains of the virus. An assortment of sequences from around the globe should help researchers to trace the spread and evolution of the virus.

Download the SARS papers by Marra et al. and Rota et al., and a related editorial.

See also translations of the news release from AAAS.

More information about SARS can be found here:

www.sciencemag.org/feature/data/sars
www.eurekalert.org
www.cdc.gov/ncidod/sars
www.bcgsc.ca
www.who.int/csr/sars/en
www.promedmail.org/pls/askus/f?p=2400:1000

—Kathy Wren

1 May 2003