How Scientists Are Engineering Allergy-Free Wheat and Peanuts

In the U.S. one in 10 adults and one in 13 children have food allergies, and the numbers are only increasing. Dubbed “the Big Eight,” a group of plants including wheat, peanut, and soybean cause 90% of food allergies, according to the U.S. Department of Agriculture (USDA).

To alleviate the problem, scientists are going to the source by genetically modifying plants to produce fewer allergens. Sachin Rustgi, PhD, assistant professor of molecular breeding at Clemson University in South Carolina, works to reduce the gluten content of wheat to make it more edible for people with celiac disease and gluten sensitivities. He presented his team’s research at the 2020 ASA-CSSA-SSSA Annual Meeting in November.

Growing up in India, Rustgi recalls people in his community experiencing “summer diarrhea” in the warmer months when people often eat wheat bread rather than corn-based bread. It wasn’t until recently that experts began to attribute the phenomenon to widespread celiac disease and gluten insensitivity. He hopes that by creating hypoallergenic wheat varieties, people can afford to consume wheat products without the need for expensive medicines.

“If we can improve the food and that will help reduce some sort of ailment that is, I think, an easy fix rather than actually finding medicines or something like that, because that adds up like to the cost of living,” Rustgi tells Verywell.

Hortense Dodo, PhD, founder and chief scientist at IngateyGen, a food tech company based in North Carolina, has been working for decades to design a hypoallergenic peanut. She says she recognizes that people with peanut allergies live a “very stressful life,” and hopes her work can alleviate some of the challenges associated with food allergies.

“We want to make sure we come up with brand new solutions to ease the tension, the dreadful fear and emotion for the families when they have a child allergic to peanuts,” Dodo tells Verywell.

Engineering a Safer Plant

When someone is intolerant of food like a peanut, people often say they simply have a “peanut allergy.” However, this insensitivity, Dodo says, can be attributed to one or several allergenic proteins in the plant. Peanuts, for example, have 16 proteins shown to cause allergic reactions.

In its effort to develop a hypoallergenic peanut plant, Dodo’s research team used a gene-editing technique to remove the major allergens, though some minor allergens remain.

“We started our work focusing on the major allergen,” Dodo says. “We do have the peanut plant that is significantly lower in overall allergenicity.”

Early efforts to genetically modify allergenic crops used a technology called RNA Interference (RNAi). This technique requires scientists to splice a foreign piece of RNA—from another plant, for instance—into the genetic code they are trying to modify. Rustgi says his team used RNAi to target and remove a gene that acted as a “master regulator” for the gluten proteins that cause allergic reactions.

Then, in 2012, researchers showed that a tool called CRISPR-Cas9, known as CRISPR, could be used to snip a section of DNA and change the code in that section. CRISPR allows scientists to pinpoint exactly which parts of the genetic code they wish to change and can do so without introducing RNA from a foreign body.

“CRISPR introduced alternative versions of the genes so you can actually create a point mutation,” Rustgi says. “That means you're not introducing, you're just changing what is naturally existing.”

Plants that are edited using CRISPR may also be approved quicker than those using older RNAi technology. “[CRISPR] is a more powerful, more precise technology," Dodo says. "In terms of regulation, it is much easier to get your product to the market in the U.S."

Appealing to the Consumer

For crop scientists, the distinction between genetically modified organisms (GMO) that use imported genetic information and those in which existing genes are changed is important for convincing consumers that modified food is safe. According to a 2016 Pew Research Center poll, 39% of respondents said genetically modified foods are worse for one’s health and only 10% say such foods are better for one’s health.

Rustgi says that though there are many people with gluten sensitivities in the U.S. who are willing to try GMO wheat, consumers in many countries around the world, especially ones with lower literacy rates, may be skeptical of genetically modified foods. Because so much American-grown wheat is exported, Rustgi says anti-allergen wheat has not yet proven to be commercially viable.

“We don't want to jeopardize our export by actually having something that the people who import from us don't like to see,” Rustgi says. “As we will see more people becoming literate in those countries which we export to, we will see this change.”

There are no genetically modified wheat products on the market yet. Gaining approval from the Food and Drug Administration (FDA) and USDA can be a long and expensive process and some consumers may have the misconception that GMO wheat actually increases gluten sensitivity.

How Hypoallergenic Crops Measure Up

Research indicates that sources of dietary fiber are important for building and maintaining a strong gut microbiome. Beneficial bacteria and other species in the gut feed off of prebiotics like the fiber in wheat.

Rustgi says that by stripping gluten from the wheat, the plant loses little to no nutritional value. Gluten, however, is essential for creating the structure and chewiness characteristic of many baked goods.

Gluten is comprised of three kinds of allergen proteins. The one that is most important for baking, called high molecular glutenin, is thought to be generally safe for people with celiac and gluten sensitivities. By removing the major allergens but keeping the high molecule glutenins in the flour, Rustgi’s team found that hypoallergenic flour produced similar results to non-modified wheat flour.

“It can bake into a reasonably quality bread—better than something that is being produced from rice,” he says.

After three years of field testing, Dodo says the allergen-reduced peanuts showed no significant difference in taste or in growth compared to commercial peanuts.

Rustgi and Dodo emphasize that when anti-allergen food products make it to consumer markets, clear labeling will be critical. Rather than simply claiming that a variety of wheat or peanuts is allergen-free would be misleading, Rustgi says, as people need to know exactly which proteins the foods contain and which are missing.

Both researchers say they hope to continue developing plants that are as close to allergen-free as possible.

“Different groups or different labs are using different tools or different technologies," Dodo says. "But I think overall everybody's concerned about bringing the solution to the problem of allergies."