New Road Map to Lethality?
The study not only doubles the amount of available genetic bird-flu data, but it greatly boosts the number of full-genome bird-flu genetic sequencessomething that has been sorely lacking.
Sequences are strings of letters that represent the structure of a DNA molecule or strand. The more scientists know about the structure of the virus's DNA, the better they will be able to fight the virus.
Fully sequenced genomes represent life-forms' entire genetic material, rather than just fragments. As such, the full sequences allow scientists to study how individual genes interact with each other.
"Individual genes don't give us the big picture," said Clayton Naeve, a genetics analyst at St. Jude and the new study's senior author.
"Basically, by looking at them in this level of detail, we're learning about their life cycle, what makes them tick, and which genes are important for which functions, Naeve said.
"That's the ultimate goal, and we're getting a better idea of how these viruses evolve."
The new genomes could help scientists learn which genes make a virus especially lethal, or which might give a bird virus the ability to move into humans.
The data have already suggested some intriguing possibilities.
"We've observed that avian viruses have a molecular characteristic that human viruses do not," Naeve said.
"That allows them to interact with human cells and potentially shut down pathways in human cells. That finding gives us a whole new means by which viruses interact with cells that we didn't understand before," he said.
"We believe this may be important in [determining] virulencein combination with other genes."
Experts continue to warn that a global pandemic could be imminent if the H5N1 virus, or another bird-flu strain, genetically mutates into a form that can be easily transferred from person to person.
Such an outbreak could rival the notorious 1918 "Spanish flu" that may have killed as many as 50 million people around the globe.
The UN's World Health Organization estimates that H5N1 has infected some 151 people to date, killing at least 82 worldwide since the first bird-human transmission in 2003.
In recent weeks the virus has spread westward from its East Asian source, killing three Turkish children who contracted the disease from infected poultry.
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