Scientists Complete Draft Sequence of Soybean Genome

A team of researchers from the United States has developed the first draft sequence of the soybean genome, an achievement that will help scientists gain a better understanding of one of the world's most important crops. Soybean is a major source of protein for food and animal feed: from tofu to soy flour, meat substitute and soy milk. It is also used to produce much of the world's cooking oil and as an important source for biodiesel. Like other legumes, the crop is also crucial for its ability to fix atmospheric nitrogen into the soil.

The team, composed of researchers from 18 American institutions including the U.S. Department of Energy Joint Genome Institute (DOE JGI), the USDA-Agricultural Research Service (USDA-ARS) and University of North Carolina, reports its finding in the current issue of the journal Nature.

"This is a milestone for soybean research and promises to usher in a new era in soybean agronomic improvement," said co-author Gary Stacey. "The genome provides a parts list of what it takes to make a soybean plant and, more importantly, helps to identify those genes that are essential for such important agronomic traits as protein and oil content."

The scientists have identified more than 46,000 genes, of which some 1,110 genes are involved in lipid biosynthesis. The soybean genome sequence has also given scientists insights into past genetic events that made the plant rich in versatile gene families. In particular, the researchers found evidences of two separate instances of genome duplication, one about 59 million years ago and the other about 13 million years ago, resulting in a highly duplicated genome with nearly 75 percent of the genes present in multiple copies.

Already, the draft sequence has allowed researchers to identify a gene that provides resistance to the Asian soybean rust, a disease that can cause yield losses of up to 80 percent. Using a comparative genomics approach between soybean and maize, researchers have also identified a single-base mutation that causes a reduction in phytate production in soybean. Phytate prevents animals from absorbing phosphorus in feed and is considered as the leading source of phosphorus pollution from agriculture.

The paper published by Nature is available at http://dx.doi.org/10.1038/nature08670 For more information, read http://www.jgi.doe.gov/News/news_10_01_13.html