A three-year grant funded by Wisconsin Partnership Program, a grantmaking program within the University of Wisconsin School of Medicine and Public Health, is backing research into how the reduction of certain proteins could be actualized through gene editing of soybean and corn, Professor of Medicine and Vice Chair for Biomedical Research in the Department of Medicine Dudley Lamming said.
It is understood that this editing could help with overall health in people with a sedentary lifestyle.
The scope of genetically modified organisms’ potential benefits for human health is expanding through research into amino acids in corn and soybean plants. Amino acids that we consume are held within proteins. Genes encode amino acids, which then make up proteins, Associate Professor of Genetics Jake Brunkard said.
“It is a little bit paradoxical if we’re accustomed to thinking of dietary protein as something that’s good for you, and there’s lots of reasons for that,” Lamming said. “There are profound benefits to eating a low-protein diet, at least, probably to the general population.”
There are 20 common amino acids, nine of which are considered essential in humans, according to an article from the National Library of Medicine database. Essential amino acids cannot be produced by the human body, and therefore must be consumed through a person’s diet. A surplus in amino acids can lead to health implications, according to the article. One such amino acid that can be restricted for a healthier diet is isoleucine.
Unlike traditional GMOs, which seek to add genes to plants for pest control, UW research focuses on the removal of genes. After the removal process, existing genes are used as a replacement. Ultimately, this substitution of genes is necessary to reduce the presence of certain amino acids, and therefore protein, Brunkard said.
Epidemiological studies have seen that populations that eat diets with higher levels of proteins tend to have increased risk for diabetes and other age-related diseases. Clinical trials have shown that when put on a protein-restricted diet people get leaner, lose fat and their blood glucose sugar declines.
“If we can change just a couple of proteins, a couple of genes that are encoding those proteins to switch around their amino acid contents, that’s enough to potentially really drastically affect amino acids in our diet,” Brunkard said.
Trials have shown when obese, sedentary mice are put on isoleucine restricted diets with the same level of calories and overall protein, they get leaner, have better blood sugar control and increased overall metabolic health, Lamming said.
In order to recapitulate this into human diets, in an approachable way, Brunkard and his lab are working to reduce isoleucine and two other essential amino acids in soybean and corn plants. Since soy and corn are so common in the American diet this would be effective for many Americans, particularly for the 70% who are considered sedentary, Lamming said.
“This is just another potential tool for people that might be able to help them lose weight, get better blood sugar control, and at least in terms of, you know, correlations, it seems like the lower your blood levels of isoleucine, the lower your overall risk of death.” Lamming said.
The application of this research on protein restricted diets is being pushed through Brunkard’s lab, which is working to reduce three amino acids in soybean and corn plants.
Currently, they are seeing reductions in amino acids around 10% but are working towards a 90% reduction. There are very few infrastructure changes that would be required to use these plants at scale — all that is needed are seeds that have the encoded genes, Brunkard said.
Americans already get a lot of their protein from soy, so the dietary adjustments would also be a relatively easy switch, Brunkard said.
“[I think] it is maybe 5-10, years or so until it really becomes a big part of the agricultural market, but it’s now the fastest growing sector and the most profitable sector of the soybean market in the world. Even in Wisconsin, it’s starting to really take hold,” Brunkard said.
The implications of this research and its potential impact are clear, Brunkard said. The sticking point is pinpointing the genetic changes that need to be made, then scaling their production.
But, there are few negative consequences — the main barrier from utilization right now is if they can limit enough protein to make a difference, Brunkard said.
“The hurdle is getting the genetics right so we have enough reduction of the protein that we don’t want in the seeds and enough expression of the protein that we do want in the seeds,” Brunkard said. “That’s our slow step. And then we think after that, we’ll want to do lots of really careful testing of these proteins in mice and then in humans.”