Searching for a soybean that doesn't contain the P34 protein which is responsible for allergic reactions in 6 to 8% of children is like looking for a needle in a haystack. But the "needle" has been found.
"After screening over 11,000 plant types from the USDA germplasm collection in Urbana, one confirmed P34 null line and approximately 91 lines with significantly reduced levels of P34 have been found," says Ted Hymowitz, a plant geneticist at the University of Illinois at Urbana-Champaign. There are about 5,000 more plant types to be tested, but the fact that one without the P34 protein has been found is encouraging.
Because soybeans are used in baby formula, a hypoallergenic soybean would help reduce the percentage of infants who have allergic responses to soy formula. An allergic response may include hives, itching, diarrhea and, in rare cases, anaphylactic shock. "The process we're using is looking for naturally occurring variants so there's no question about the safety of it. We're providing an alternate approach to genetically engineering for a P34 null line," Hymowitz says.
Although a soybean without the P34 protein could be produced using biotechnology, concerns about the use of transgenic ingredients in baby food may make people worry. "While there is no cause for concern in using biotechnology in baby food, people do worry and may not buy it," he says.
After all of the plant types have been tested, the next step will be to transfer the trait that suppresses the P34 protein into a high yielding, disease-resistant soybean cultivar. The first soybeans to be tested were those that are currently grown commercially. They all contain the P34 protein.
Hymowitz notes that eliminating the P34 protein doesn't affect the nutritional content of the soybean.
The testing process is slow; only 100 plant types can be tested each day. "We're doing the qualitative analysis. Does it have the protein or doesn't it? It's a dominant protein, so it's rare to find ones that don't have it," says Hymowitz. "The ones we find with little or no P34 are sent to Eliot Herman's USDA lab at the Donald Danforth Plant Science Center in St. Louis, Missouri. They do the quantitative analysis."
Leina Mary Joseph is in charge of the tedious task of testing the seeds using immunological procedures. "The Danforth lab uses a different technique to confirm that the result we got is accurate," says Joseph. "We found a null that doesn't have any of the P34 protein and it has been confirmed by their lab. We are already growing some of the null and low P34 protein lines in the greenhouse so we'll have a good supply of seeds when we need them."
The research is being led by Ted Hymowitz of the University of Illinois and Eliot Herman at the Danforth Center. Hymowitz is a nationally recognized soybean geneticist. Herman is a molecular biologist with the USDA Agricultural Research Service, and adjunct professor of Plant Science at the University of Missouri, who is located at the Danforth Center through a joint agreement between the Danforth Center and USDA. Leina Mary Joseph (U of I) is a co-investigator on the project.
Funding for the project is provided by the Illinois-Missouri Biotechnology Alliance, with a special grant from USDA.