“It’s an absolute revolution!” insists Bruce Whitelaw, Professor of Animal Biotechnology at The Roslin Institute, Scotland, of gene editing. “Scientifically, the potential is huge. It allows us to increase the genetic variations from which producers can select animals with traits they want to promote.”
Whitelaw and his team recently announced the potential to insert a variant of the RELA gene from warthogs and bush pigs into domestic pigs, which could make the latter resistant to African swine fever, a nasty and often deadly disease. Genus/PIC (at the behest of Graham Plastow, now Gentec CEO) funded the preliminary work to find the genetic variation many years ago but the project stalled for lack of technology to develop it. It has only now borne fruit because gene editing came along as the enabler. Other recent gene edits in pigs include the generation of GDF8 (myostatin) mutants to increase muscle, and resilience to diseases such as PRRS and foot and mouth disease.
This is gene editing as Whitelaw intended—with major application in resilience to disease, which is a major burden in livestock. Other applications he foresees include reproductive efficiency (increasing the number of females who bear multiple offspring, for example, rather than increasing the number of offspring per gestation) and gender selection, which is particularly important in the dairy industry where male offspring have little value, and which has been difficult to achieve beyond the sexing of semen. Farther down the line, it may be possible to introduce heat or drought tolerance from indigenous animals into mainstream animals, therefore expanding the footprint of livestock around the world. Used in this way, gene editing will help satiate the growing human population’s desire for animal protein.
But will producers want to use it?
“Producers are chasing it!” says Whitelaw. “What industry partners have to do is demonstrate applicability. The University of Missouri showed that you could edit variation into gene CD163 and create PRRS resistance in pigs. (Ed: Gentec reported this in our December newsletter. See source article here). Now, the task is to take that project, make sure the trait has no deleterious effects on other traits and show its true utility.”
And the Number One question since, if consumers don’t buy the product, it’s all moot—will they understand the difference between gene editing and genetic modification? The latter has had a rough ride over the years. Introducing transgenics didn’t go down well. Special-interest groups focused on nebulous health and environmental effects.
Gene editing, on the other hand, produces simple base variations that can happen naturally. Using Whitelaw’s RELA project as an example, the variation of that gene in warthogs and bush pigs may well appear in domestic pigs naturally—but evolution moves at glacial speed. Given the increasing global population, humans can’t wait that long. One person in seven is malnourished today. By the time we reach 9 billion, that figure is expected be one in three if we don’t increase production of agricultural protein. Genome editing can slash the standard 20+ generations of breeding required to introgress a gene allele back to just one; and eliminate evolution’s lop-sided variety in favour of specific alleles that increase food value.
For consumers to buy in to gene editing, two things have to happen in parallel: a full discussion with regulatory authorities to put in place an appropriate regulatory pathway to take the technology to market; and another full discussion—this time with the public—to convey that this is a good, safe technology.
“Gene editing does exactly what it says on the can,” says Whitelaw. “Every offspring carries mutations that neither the dam nor the sire has. Some are good, others not. Evolution selects the good ones. We’re doing exactly the same thing, except that we know the change is beneficial. Individual animals will be more robust, less sick and therefore have a better quality of life. That has to be a good thing at every level.”