b'Unsticking A Sticky SituationWith low viscosity wheat, distillers are about to find a solution for their sticky mess.Alex MartinHAVE YOU EVERstopped to think what a day in the life ofgenes were responsible, they did so by suppressing the genes in a Scottish whisky distiller was like? Or what it would be likeGM wheat and created wheat with low arabinoxylan content in to use wheat as a base for your whisky? The answer is probablythe grain. And things started falling into place.not. We showed that when you suppressed these genes that Distillers have encountered one unique problem when work- produced the arabinoxylan in GM wheat, you also get a reduced ing with wheat to make whisky. Most soft wheats that are used inviscosity, he says. Since we knew viscosity was an undesirable distilling have a fatal flaw: high viscosity.trait, we got in contact with both Limagrain UK and the Scotch If wheat is too viscous, the material can clog up the machin- Whisky Research Institute (SWRI) to look at potentially commer-ery because it becomes sticky, says Rowan Mitchell, plant biolo- cializing the gene discovery, this time by using non-GM, tradi-gist at Rothamsted Research.tional breeding approaches to suppress these specific genes.Now, while high viscosity isnt a deal breaker, it can causeMitchell mentions that genetic improvement normally occurs some sticky situationsliterally. Normal wheat, when fer- by screening huge numbers of plants for the trait (in this case mented, can turn into a complete sticky mess. Meaning, occa- viscosity) and then selecting the best and breeding from these, sionally, you have to shut down to clean up the equipment. a very slow process which often does not yield significant Grain distilleries run 24-7 and so shutting down stills forimprovement. But here the group actually started with knowl-cleaning leads to significant losses in alcohol production, saysedge of what the gene did and screened DNA sequence to find Simon Berry, wheat MAS project leader of Limagrain UK.variants in ita reverse genetics, approach (i.e. to go from Thats where a partnership with Rothamsted Research andcandidate genes involved in arabinoxylan biosynthesis to the Limagrain UK formed. Both Berry and Mitchell saw a need todesired phenotype of a low viscosity wheat ideal for distilling). identify a trait to lower viscosity in wheat to make the distillingHowever due to the nature of the wheat genomewhich has process better for distillers.three copies of every geneit was a difficult process to sup-The project actually started out in the complete oppositepress the arabinoxylan. direction than this application, Mitchell says. Originally, theWe used an approach called TILLING which allows us to interest started in dietary fiber for wheat grain, which would befind non-functional variants of the three copies of the gene that beneficial for humans eating wheat. However, its also known thatmakes arabinoxylan, Mitchell says. We then combined these dietary fiber gives rise to this viscosity problem. three, novel gene variants into a new non-GM wheat line which Mitchell says they were interested in trying to figure out thedid indeed have the low viscosity, as we predicted.genes responsible for making the main type of dietary fiber inThe TILLING population was created in a U.K, bread-making wheat, a molecule called arabinoxylan, to make a healthier breadvariety, says Berry. For distilling, you need this low viscosity for human consumption. When they tried to prove that certaintrait in a soft wheat, low protein background, and it takes a lot of 36/ SEEDWORLD.COMINTERNATIONAL EDITION 2021'