Creating Low-Gluten Bread Made Possible with Gene-Editing Technique

Gluten-free bread is a type of bread that doesn't have any wheat, barley and rye, and instead has a combination of starches like potato flour, cornstarch and rice flour. As there are people who experience adverse reactions whenever they consume food that contains gluten, gluten-free bread is considered to be an ideal choice for those who suffer from celiac disease or are sensitive to gluten. But, here's some good news! Scientists at the Institute of Sustainable Agriculture have created a strain of wheat that is low in gluten content, of which may soon be safe for celiac patients.[1]

For those who have already tried gluten-free bread, they would all probably agree that it can be a terrible option at times, as gluten is what provides the bread that light yet firm texture that people all know and love. Fortunately, scientists have discovered a way to fix it. The team of Spanish scientists made use of CRISPR, a gene-editing technique, in order to develop a crop that can then be used in making low-gluten bread in the future.

The said technology allows the scientists to remove the gene sections that initiate an autoimmune response among patients who are suffering from celiac. In a strain, they were able to delete 35 out of the 45 genes that code for a gluten component responsible for the intolerance towards gluten. Through this technology, the scientists were able to create new wheat strains that reduce the risk of people with celiac experiencing immune reactions from consuming it.

But, how? Well, most reactions from gluten are caused by gliadins and so, these scientists have started working on gene-editing just to remove the gliadins from the wheat.[2] They aim to produce a plant that can make flour to be used in bread that is considered safe for people who would usually avoid it. At present, the wheat strain has undergone small trials in Spain and Mexico. So, people may just need to wait a few more years before they can eat wheat-based bread that is gluten-free.  

However, Sarah Sleet, Coeliac UK’s chief executive, believes that this might not help in reducing the symptoms of celiac, especially since each individual has different gluten intolerance-causing protein component. She also added that some work still needs to be done just to prove that the product would be safe for everyone who has celiac disease.

So, before it's widely available for use, there definitely needs to be more trials to see just how effective this wheat-based bread would be for celiac patients. But, this is a step in the right direction, no matter how small it may be.

What is CRISPR?

CRISPR is basically a technology that is used to delete or modify genes to make crops resistant to pests and to reduce the spread of livestock diseases. Apart from that, CRISPR is also used to increase the sustainability and nutritional value of the crop. It is now seen as a method of editing crop genes so that they can better resist diseases and changes in the weather. The CRISPR technology can also be used to produce more tender meat and more flavorful vegetables, which can help to improve food safety through knocking out resistance to antibiotics and through prolonging its shelf life. Hence, reduction of food waste also becomes possible.

According to Heike Sederoff, a system and synthetic biology professor, plants are also like animals. They have a lot of genes in which they don’t know what most of them do and the reason why they are there. This is where CRISPR makes it easier on their part. It allows them to know and understand the thousands of genes in plants by either taking out or deleting a specific gene. It also allows scientists to remove whatever gene they don’t want so that they can improve the quality of the products produced.

The use of CRISPR in food production

Well, this is not the first time that the technology has been used in producing food. In fact, it is being used in preserving food today. The USDA or the US Department of Agriculture has even approved the CRISPR-edited crops, including a mushroom that was edited genetically, to resist browning by deleting a gene for an enzyme that causes it. When browning is prevented, it can improve the texture and the flavor of the food. The mushroom was the first crop that has not been subjected to regulation for the reason that it does not contain foreign DNA nor would it be a threat to other plants unlike others that the USDA regulates. This is because they are tweaked inside a lab to contain DNA just to make them resistant to pests.

What happens when a celiac patient consumes gluten?

When a celiac patient consumes gluten, they would experience nausea, headaches, tiredness, bloating, and diarrhea. This means that the patient needs to avoid consuming gluten including oats so that their gut can heal. A gluten-free diet is the only treatment for the said disease, and typically, it would take 6 months to 5 years for the gut damage to be completely healed.

A person who is on a gluten-free diet can eat any food as long as it does not contain gluten like fish, meat, potatoes, rice, and lentils. For drinks, they can still have flavored water, cider, wine, and fruit juice. Sadly, they should avoid drinking beer, stout, and lager at all cost. On the other hand, there are also now gluten-free products like pasta, biscuits, crackers, and of course, bread that can be easily purchased in grocery stores.

Gluten-free bread for celiac patients

Gluten is the protein that can be found in wheat. This allows the food to retain their shape, acting as the glue that holds it together. It is primarily composed of glutenin that affects the elasticity of the dough and gliadin, which allows the bread to rise during the baking process.

Gluten is actually not bad, but it can create an unwanted response in people with celiac as it produces damage to their intestines. As a result, their body is not able to absorb all the vital nutrients that it should be getting. After all, it is a disease that affects 1 out of 141 people in the US. For this reason, doctors recommend these people the gluten-free diet so they can avoid any further damage to their intestines.

On the other hand, wheat grain contains many gliadin genes, which makes it impossible to attain gliadin-free wheat using the classic breeding methods. So, Barro’s team has used the CRISPR technique in order to remove most of the gliadins that can be found in wheat through adding genes that initiate the RNA interference process. Out of 45 gliadin genes, they were able to mutate 35 of them. Not only that, they were also able to reduce the toxicity of wheat up to 85%.

This allowed for the production of some specific proteins to be prevented. However, as the gliadins are still intact, the risk of the wheat producing that protein again is still there. So, the team has decided to eliminate the genes completely. However, the wheat is still not suitable for those with celiac as it still has some gluten in it, but people who wanted to reduce their gluten intake can use this wheat for making rolls and baguettes, as making large loaves is still not possible with it.

Nevertheless, Barro said that they are already working on the remaining gliadin genes in the wheat, and they are in high hopes that they would be able to get rid of the remaining 10 genes so that it would not be able to produce gliadins anymore. If everything goes according to plan, consumers can expect more gluten-free products to appear in grocery stores soon.

Citations:

[1] https://www.ncbi.nlm.nih.gov/pubmed/28921815

[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5253684/