
Human Genome Project Aids Soybean Genome
MappingBy Don Comis April 22, 1999What's the difference between a
soybean and a person? Besides the obvious, soybean plants have three fewer
pairs of chromosomes--and about 1.7 billion fewer pieces of DNA. Still, plant geneticist Perry B. Cregan borrows biotech tools from the
human genome project to map soybean
genes. Cregan is with USDA's
Agricultural Research Service in
Beltsville, Md. The United Soybean Board has
awarded more than a million dollars in grants to support soybean gene mapping
by Cregan and other scientists around the country. Finding soybean genes to
enhance yields and pest resistance could eventually lead to raising U.S. yields
by several hundred million bushels a year. Recently, Cregan found map markers near the first two of the four genes he
thinks give the plant resistance to cyst nematodes. These microscopic
roundworms rob farmers to the tune of 220 million bushels a year. He and
University of Minnesota colleagues are
seeking markers for the other two resistance genes. One of the biotech tools from the human genome project is called
"simple sequence repeats." Cregan and Nebraska colleagues are using
it to search for yield-boosting genes in a wild ancestor of soybeans. With simple sequence repeats or SSRs, the scientists can draw maps that
allow them to systematically search for useful genes in the genome one section
at a time. With SSRs, the scientists have developed more than 300 lines of soybeans in
which one-eighth of the original genome has been replaced by wild DNA
fragments. These lines are fertile breeding ground for finding yield-boosting
genes. Scientific contact: Perry B. Cregan, ARS
Soybean and
Alfalfa Research Laboratory, Beltsville, Md., phone (301) 504-6070, fax
(301) 504-5728, [email protected].
U.S. Department of Agriculture | |