Scientists Unlock Genetic Information on

THURSDAY, Jan. 26 (HealthDay News) -- Researchers are reporting the most complete analysis yet of the genetics of bird flu viruses, including the dreaded H5N1 strain whose spread to humans is feared as the potential cause of a pandemic.

"By collecting blueprints of several hundred flu viruses, we have data that might tell us more about what genetic features are required to move a virus out of birds into humans, and which genes are important in things like virulence," said Clayton W. Naeve, director of the Hartwell Center for Bioinformatics and Biotechnology at St. Jude's Children's Research Hospital in Memphis, Tenn.

Naeve is the lead author of a report on the viral genetics work, published in the Jan. 28 issue of the journal Science.

"There have been other bird flu virus genomes done, but we in this study doubled the amount of information available," Naeve said. "We report 2,169 new bird flu genes and 169 complete genomes for various bird flus. This is a significant contribution to our knowledge about this population of viruses."

The data is being made available to the research community through the U.S. government's National Center for Biotechnology Information, said John C. Obenauer, an associate research scientist at the St. Jude's center.

There's no direct application of the new genetic information to stopping the spread of bird flu, which is also called avian flu, Naeve said.

"But we have learned more about how these viruses act, and how they interact with human cells," he said. "The more we learn about how viruses act, the more likely we are to come up with interventions that block the virus or treat an infection if it occurs."

The journal report includes "several testable hypotheses, and we hope the research community takes us up on that," Obernauer said.

The St. Jude's researchers used a technique they call "proteotyping" to look for differences in proteins -- specifically, variations in the sequence of amino acids that make up a protein.

They have identified a special version of a protein called NS 1 that may allow a bird virus to attack human proteins. The NS 1 proteins in viruses that cause low-mortality outbreaks are clearly different from that in the deadly H5N1 virus, they found.

"This finding reveals an entirely new means by which avian flu virus may interact with host cell proteins, and these proteins may prove valuable as targets for antiviral therapy," the journal report said.

"Perhaps this can account for the virulence of the virus," Obenauer said. "We hope that the research community follows up on that."

Bird-to-human infection with H5N1 has caused an estimated 80 deaths worldwide, with most of the infections occurring in Asia, although Turkey just reported an outbreak that sickened 21 people and killed four children.

While the virus hasn't shown the ability to easily infect humans, health experts worry it could mutate to a form able to pass between people, leading to widespread sickness and death.