Photograph by Henry Genthe
Biologist J. Craig Venter, the scientist who beat the federal government in the race to map the human genome, has turned his attention to the seas. His message is that the genetic diversity in the oceans is far greater than expected, dwarfing the diversity within human DNA. To prove his point, Venter pulled a sample of water from the seemingly barren Sargasso Sea off the coast of Bermuda and isolated 1.2 million new genes and 1,800 never-before-identified marine microbes—a mother lode that already exceeds the number of genes from all species recorded in public databases.
This time, Venter has the Department of Energy on his side. He’ll need the help: He plans to catalog all life in the sea by circumnavigating the world in his research yacht and stopping every 200 miles to collect samples. As when he worked on the human genome, Venter is relying on a radical technique called shotgun sequencing: He chops up vast amounts of DNA into tiny pieces and then uses sophisticated computer analyzers to piece them back together into intelligible genes and chromosomes. In this case, however, Venter will be looking not at one organism but at thousands or millions at a time. Making sense of all that information will require vastly more complex computer programs and mathematical techniques.
Department of Energy researchers hope the work will turn up novel microbial chemical reactions that could aid energy production, pollution cleanup, or the manufacture of new drugs. But Venter insists his primary goal is pure discovery. “It’s amazing how little we know,” he says. “Less than 1 percent of marine microbes have been characterized. We’re looking for life on Mars, and we don’t even know what’s on Earth.”