Low Gluten and Coeliac-Safe Wheat through Gene Editing

Cereal consumption by humans is older than agriculture. During preceding eras, humans gradually acquired the necessary knowledge and tools for processing and cultivation of cereals, making themselves unconsciously prepared to become the first farmers when climate improved at the end of the last Ice Age, some 12 thousand years ago, in the Near East (Fertile Crescent) region. Early wheat cultivation in fields surrounded by wild relatives facilitated the occurrence of interspecific hybridizations; one of the resulting hybrids was bread wheat, with superior nutritional and food-technological qualities, largely due to the favourable composition of the gluten proteins in the grain. Bread wheat developed from that time into the commodity crop that it is nowadays.

Wheat-based foods and food with wheat ingredients can provoke coeliac disease in genetically predisposed susceptible individuals representing 1–2% of the population. Some specific digestion-stable fragments of wheat gluten are recognized by immune cells that become inflammatory in the small intestine, ultimately resulting in a variety of severe symptoms. The large number of gluten genes in wheat’s complex genome hinder conventional breeding to produce a coeliac-safe wheat while maintaining good baking properties, although low gluten levels can be reached. CRISPR/Cas9 enables now to produce wheat line that potentially have a strongly reduced coeliac-immunogenicity, as will be explained from two model studies. An efficient screening pipeline to detect and select promising coeliac-safe(r) wheat lines will be described. Legal and societal aspects regarding the (non) GMO status of gene-edited plants, gluten-free food production chain management, and food labelling will be discussed.