Malaria Genome Research Brings New Hope ; over 30 Studies This Week Highlight a New Approach to Infectious Disease: Genomics

Article excerpt

Efforts to battle infectious diseases in developing countries have crossed what many see as an important threshold with this week's unveiling of the genetic blueprints for two key malarial agents.

International teams of scientists have sequenced the genomes of both the parasite responsible for malaria infections in humans and of the mosquito that carries the parasite.

Armed with this information, scientists hope to unlock the biochemical workings of the parasite and better understand its interactions with mosquitoes and humans. That information can then be used to develop new drugs, vaccines, and control strategies that could dramatically reduce the disease's reach.

From 300 million to 500 million people a year contract malaria, which kills as many as 2.7 million people annually, according to public health officials.

Collectively, the genomes represent "a major milestone," says Regina Rabinovich, director of the Malaria Vaccine Initiative. "This is precisely the research we need to have happen."

Genomics breakthrough

The six-year, $17.9 million gene-sequencing work, led by labs in the US, Britain, and Australia, also highlights the increasingly important role genomics is playing in biomedical research.

Armed with cheaper, more efficient, and faster machines and computers, scientists are sequencing the genomes of a range of other infectious disease agents, many of which take their highest toll among developing countries.

"There will be many more of these genomes to follow," says Malcolm Gardner, a researcher at the Institute for Genomic Research in Rockville, Md., and leader of the group that sequenced the parasite's genome.

The researchers sequenced the genomes by separating the organisms' chromosomes, long chains of DNA organized into genes. The chains were randomly broken, and each segment was inserted into bacteria and cloned. The segments were analyzed to tease out the patterns of DNA's four chemical "bases." The teams then used computers to sort through the information from the segments and put the genetic Humpty Dumpty back together again in a virtual form.

The reassembled sequences were then checked for accuracy, Dr. Gardner says, yielding a "final draft" of the parasite genome that is 98 percent complete.

The work on malaria is being reported and analyzed in more than 30 papers appearing in today's edition of the journal Nature and tomorrow's Science. …