Thursday, February 23, 2017

Comments on Rules for Gene-Editing Technology

From the literature:

“We found that the improvement of a plant variety through the acquisition of a new desired trait, using either mutagenesis or transgenesis, may cause stress and thus lead to an altered expression of untargeted genes. In all of the cases studied, the observed alteration was more extensive in mutagenized than in transgenic plants” - (Batista, et al; 2008)

So what are the implications of this? Currently the FDA is accepting public comments related to genome editing in new plant varieties used for foods.

Gene editing represents an opportunity to move forward with advanced technologies to sustainably feed the planet without the same regulatory hurdles that make development costs for transgenic plant varieties (aka GMO) up to 20x greater than conventionally bred plants(Conko and Miller, 2003). Similar to organically certified crop varieties that use chemical and radiological methods to create in-genome changes, gene edited technologies operate within genome, vs. across species.  (one popular example of gene editing includes the CRISPR-Cas9 system).  Unlike mutagenic approaches used in organically approved plant breeding systems,  these in-genome tweaks are planned, controlled, and designed to bring about very specific outcomes. Gene edited plants are not ‘gmo’ in the manner that the term has traditionally been used (or misused) by regulatory proponents, and in fact are just as natural as their organically approved counterparts in terms of their development. However they stand out in very important and positive ways.

The article above (see also Baudo  et al; 2006) does not specifically address gene edited plants, while it does indicate that genomic disruptions are greater in mutagenic plants vs standard transgenic plants. (one common argument for increased regulation related to transgenic crops has been based on the concern that the introduction of new genes can have unknown consequences and genomic disruptions are one way of characterizing this*) With greater disruptions, one might favor increased regulatory scrutiny similar to the existing framework in place for transgenics. However, we do not have a framework in place for mutagenically improved crop varieties that have been safely used for decades and approved by the organic food industry as well as consumers.  Because both mutagenic and gene edited technologies represent similar in-genome approaches to crop improvement, this in fact argues against additional regulation for both mutagenic and gene edited plants, or it begs for the possibility of a revision of the existing regulatory framework for transgenics.

The benefits of gene editing technology offer far greater option value* than either conventional and organic mutagenically improved or even traditional ‘GMO’ or transgenic crops while the risks to human health and the environment are equally minimal. To impose new costly regulations on gene-edited plants would be to create huge hurdles for the development of next generation green technologies in food and fiber production in the United States and have significant environmental, public, and personal health implications for the rest of the world.


Batista R, Saibo N, Lourenço T, Oliveira MM. Microarray analyses reveal that
plant mutagenesis may induce more transcriptomic changes than transgene
insertion. Proc Natl Acad Sci U S A. 2008 Mar 4;105(9):3640-5. doi:
10.1073/pnas.0707881105. PubMed PMID: 18303117; PubMed Central PMCID: PMC2265136

Baudo MM, Lyons R, Powers S, Pastori GM, Edwards KJ, Holdsworth MJ, Shewry PR. (2006). Transgenesis has less impact on the transcriptome of wheat grain than conventional breeding. Plant Biotechnol J. 2006 Jul;4(4):369-80

Henry Miller and Gregory Conko. Bootleggers and Biotechs. Regulation. Summer 2003

 *this post has been modified to better clarify some posited arguments some have made for regulation of genetically modifed crop plants as well as to express the potential option value that gene editing might provide in addition to previously existing technologies. Special thanks to input via twitter from @CosmicHominid for constructive input

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