USDA Proposes Ambitious New Plant Genome Initiative

WASHINGTON-In an ambitious answer to the National Institutes of Health's Human Genome Project, the U.S. Department of Agriculture has sprouted plans for a parallel project to map the genetic structure of key food plants. The proposal, presented by USDA program manager Jerome Miksche at a meeting of the NIH genome project's advisory committee in June, would identify genetic traits that can increase yield and disease resistance. The price tag is estimated to be $500 million over 10 years. In recent months the agency has created a new Office of Plant Genome Mapping within its Agricultural Research Service (ARS). At its helm is Miksche, national program manager at ARS. State and federal agencies spend about $10 million annually on plant genome research, about a third of which comes from USDA. The new proposal would boost USDA's contribution nearly 15-fold, to an estimated $50 million yearly. Although plans are still preliminary, many supporters expect the expanded USDA genome project to be linked to a $500 million-per-year competitive grants program recently proposed by the National Academy of Sciences' National Research Council (NRC) and independent agricultural organizations. That effort, which would boost the department's overall basic research budget by more than 50%, is itself a response to persistent criticism that the department has failed to support cutting-edge research. The competitive grants programs, backed by new assistant secretary for science Charles Hess, was endorsed in an NRC report issued in June. While it has broad support among the agricultural community, the proposal could face serious opposition within Congress, which has traditionally played a large role in determining the department's research priorities. As a first step, supporters have begun to lobby administration officials to include both proposals in the president's 1991 budget being assembled this fall for submission in January. The plant genome project, like the larger competitive grants proposal, will primarily fund peer-reviewed research from non-USDA scientists. That process, common to agencies like NIH and the Department of Energy, represents a new direction for USDA, which has historically spent most of its research dollars in-house through its network of laboratories and extension stations at state land-grant colleges and universities. The new approach was applauded by scientists attending the human genome meeting at NIH, who saw it as a way to bring plant genome research in line with the standards of peer review. "It looks like the Human Genome Project, if nothing else, has opened the USDA to real science," said human genome advisory committee chairman Norton Zinder of Rockefeller University. Although USDA's Miksche stresses that his project is not a "me too" response to the NIH effort, which is expected to cost as much as $3 billion over 15 years, he agrees that the human genome project provides one of the strongest reasons for a major initiative at USDA. Researchers on plant genetics expect to reap the windfalls of the explosive pace of gene mapping and sequencing technology-a revolution fueled in large part by interest in the human genome-by being able to use many of the same machines and automated techniques as human genome researchers. "The technology overlaps almost completely," says Du Pont biologist Scott Tingey. In many ways, mapping the genetic complement of a dozen or so important crop plants may prove easier than exploring the prototypical human genome. Ethical questions relating to altering an organism's genetic composition-a topic that often raises the specter of eugenics in human genome studies-is not a problem in agriculture. "You can create 'model' genetic systems in plants that you just can't do in humans," says Tingey. Furthermore, the ability to breed vast numbers of genetically identical plant samples offers a statistical payoff that can speed research by reducing uncertainty. Nevertheless, deciphering the genetic makeup of as many as 15 species of plants, a group that will likely include corn, soybeans, and tomatoes, is a formidable task. The corn genome, for example, is about five times the size of a human's. For that reason, the project will likely not "sequence," or identify and order, every one of the genome's base pairs. Rather, scientists will concentrate first on mapping the location of key genes that are believed to improve productivity. Ideally, the information that emerges as full genetic complements are mapped will also prove useful in other species. "We'll look to see if certain traits are common between species," says Calvin Qualset, director of the University of California's genetic resource and conservation program and an organizer of a new independent international collaboration to map the wheat and barley genome. Among the possible shared attributes that Qualset and other plant geneticists will search for are such single-gene traits as resistance to a particular disease and such complex, multigene traits as the ability to withstand drought or high levels of soil salinity. "We hope to be able to pinpoint the genes that are responsible for things like heat tolerance and then engineer them into other plants," explains USDA's Miksche. Japan already has plans for a $200 million rice-genome project, and the British government is preparing a $12.5 million assault on the wheat genome. Miksche warned the human genome planners that foreign projects are likely to lead to "formidable competition in the [international] marketplace for U.S. agriculture" unless the U.S. mounts a comparable effort and, at the same time, is willing to cooperate with other countries. "Mapping the genome of higher plants will be very, very costly," he said. "It's obvious that foreign collaboration will be necessary." Discussion of the plant genome initiative will continue later this month, when the program's advisory committee meets to set the goals, scope, and timetable of the project. While some aspects of the effort will likely be modified at the meeting, the overall concept appears to have broad support: "Some of our dreams may be shattered," Miksche says, "but I am nothing but optimistic."

USDA Proposes Ambitious New Plant Genome Initiative

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