b'The Uses of Gene Editinga PerspectiveTHE CURRENT DISCUSSIONon New Breedingnity to add missing alleles in our adapted germplasm Technologies mainly focuses on targeted mutagen- pool. This is where the technology will shine: bring esis or gene editing, more recently labeled as Newtogether alleles of interest by recreating them in the Genomic Techniques. This includes technologies,appropriate germplasm. The more complex the con-such as Zinc-Finger Nucleases (ZFN), TAL Effectortext, the more advantages the technology brings. Nucleases (TALEN), CRISPR-Cas and its derivatives,This complexity can take two main forms, either and Oligonucleotide Directed Mutagenesis (ODM).in the genetic complexity of the recipient, or in the All these share three elements: targeting anumber of genes to be modified to obtain a given sequence, inducing some form of DNA damage ateffect. Examples of the genetic complexity would be that sequence and using cellular repair to create athe need to get all six copies of a gene in hexaploid JEROEN WILMERmutation. They create small modifications in individualwheat modified to obtain a phenotype, or the crea-is a Research &genes without other DNA modifications elsewhere intion of disease resistance in vegetatively propagated Technology managerthe genome, combining the type of modifications fromtriploid Cavendish banana. in Plant Biologytraditional mutagenesis with increased precision. The question of number of genes to be modified to and was involved inBut what are the perspectives for gene editing create the trait is currently the big unknown and may developing businesstechnology? Do they merit the long and difficultbring the biggest advantages for genetic improve-models for CRISPR- debate to update regulations, create the necessaryment. What if we would be able to create targeted CAS use for a seedsupporting technologies to make them truly genericmutations in 20 or 30 genes that we suspect are company. and make them accessible to everyone interested ininvolved in a complex but fundamental trait in our crop genetic improvement?and we could start breeding with this material? We A first approach is to look at the products createdwould remove all the genetic noise from the multiple, as these determine the potential application value.often less adapted, donors of the alleles and could Most of the initial traits being created are very similar toproperly evaluate the trait in a large population carry-traditional mutations: gene knock-outs for qualitativeing all the various combinations of our selected genes. traits such as waxy and high-amylose starch in This should allow us to improve the genetic gain in cereals, color in some vegetables, as well as some dis- the breeding process dramatically. This could provide ease resistances.our best chance to advance towards sustainability With the more advanced technologies, we cantargets set for 2030 in the EU Green Deal.create more specific modifications of genes otherFor the moment, some countries accept traits cre-than loss of function. However, these technologies willated by some of these technologies as non-GMO and not create new genes, so no equivalent of Round-upthus non-regulated, but not other technologies, with Ready herbicide tolerance or Bt-like insect resistance.different levels of scrutiny in different countries. Other Generally, the traits obtained are likely similar to thoseareas, like the EU, refuse the use of any of these tech-created by allele introgression, either from wild materialnologies outside a GMO-framework. or mutagenized populations, and there is most likelyGiven the limited added value I foresee, the wide-little additional added value in the products beyondspread use of traits created by gene editing will prob-that already known.ably only work if we move to a low cost, trait-based The second angle is to see where we can use theseevaluation instead of the technology-based evaluation technologies in our process and if there is any addedas currently used in Europe. The key to such a system value in this area. Smart use of gene editing may allowis the acceptance that mutations are the same, which-us to create desirable mutations in adapted germplasmever the way they were created, if the final sequence is without the long and onerous work of recurrent back- the same. crosses to remove unwanted other characteristics fromNow theres an idea. SW the allele donor: a gain in efficiency and the opportu-152/ SEEDWORLD.COMDECEMBER 2021'