Gene Editing

Cutting-edge “gene editing” technology is giving scientists an ever-increasing ability to manipulate DNA, the basic building block of life - to literally ‘cut and paste’ specific genes into or out of an organism’s genome to bring about a desired result. This month alone, US researchers reported the first successful attempt to modify DNA ‘in vivo’ (in a living being) in non-dividing adult cells - that is, those found in the brain, the eyes, the heart and the liver of mature organisms. Similar research could, in future, lead to new treatments for age-related diseases and even allow the human lifespan to be prolonged. So is this the first step towards a world in which previously incurable genetic diseases are eradicated, where malnutrition is banished forever by genetically-enhanced crops, or where species currently on the edge of extinction are saved by genetic intervention? Or, as opponents of genetic engineering might claim, is this merely the first blind stumble down a slippery slope leading to uncontrollable “genetic pollution” of the living world by scientists playing God with natural forces they do not fully understand? According to the Royal Society of New Zealand (RSNZ), the rapidly accelerating revolution in gene editing technology has huge implications for the world and for New Zealand, with the need for informed public debate becoming ever more pressing. To meet this need, the society has just convened a multidisciplinary panel of experts to consider the ethical, environmental, economic, regulatory, and socio-cultural impacts this biotechnology might have on New Zealand. In announcing this panel, RSNZ President Richard Bedford said important legal and ethical decisions had to be made about the use of gene editing, and about “where New Zealand’s boundaries are for adoption of these technologies and the speed at which we wish to adopt them”. Overseas, gene editing has been touted as having the potential to create crops adapted to climate change, to wipe out disease-carrying insects, and, in humans, to cure genetic disorders such as Huntington’s disease. Possible uses for the technology in New Zealand, meanwhile, include modifying cows to produce less methane, or in pest control for conservation purposes. Co-chair of the RSNZ panel Barry Scott said healthcare and agriculture were two important areas where gene editing technology might be applied, with conservation being another potential area with particular relevance to this country. “Interest in using gene editing to introduce a sterilisation gene into a pest as part of a pest-eradication programme is understandably high in New Zealand, given the challenges facing our biodiversity” . However, Scott, a Professor of Molecular Genetics at Massey University, also pointed out the problems the new genetic techniques posed for New Zealand’s existing regulations on genetically modified organisms (GMOs). “It is now becoming [difficult] to distinguish between genetic changes generated by conventional breeding, gene editing, or natural mutation, which may make the new gene-editing technologies difficult to regulate,” he said. At present, research on GMOs is strictly controlled, with the rules regulating field trials being particularly stringent. Conventional selective breeding of plants and animals has been practiced by humans for millennia, with many existing species being radically changed from their ancestral forms. The cobs of modern maize, for example, are ten times larger than those of the original wild ancestor. And since the 1930s, new crop varieties have been deliberately created by radiation ionizing and chemical methods, although, like standard artificial selection, this too relies on random genetic mutation, only some of which might prove beneficial. By contrast, modern gene editing technologies, of which CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) is the most well-known, allow for targeted modification of specific genes within an organism’s genome. In other words, scientists can now switch particular genes on or off, or delete them or replace them with different genes at will. These technologies, whose costs have fallen dramatically since they were first developed, are already widely used in medicine and food production overseas. Many in New Zealand’s agricultural sector also see huge potential benefits in using similar techniques to improve yields, say, or to reduce the environmental impact of farming practices. Federated Farmers President William Rolleston, for example, has repeatedly called for the stringent regulations on the use and definition of GMOs to be reviewed. By contrast, many in the environmental movement remain wary of using such biotechnology, especially while it is so new and untried. The Green Party’s policy on genetic technologies, for instance, advocates use of “the precautionary principle on a case by case basis, so long as [the technologies] are contained within the laboratory and are not applied to food production”. Internationally, Greenpeace and other environmental groups have long campaigned against the use of genetic engineering in agriculture. University of Canterbury philosopher Doug Campbell, who is researching the ethical implications of genetic technology for conservation purposes, agreed that a precautionary approach to genetic technology was necessary, most especially “because the risks of real harm to our ecology, food supply and national reputation are very real.” However, Campbell also accepted that estimations of the risks from biotechnologies needed to be based on sound science. “The mere fact that it is genetically modified does not in and of itself provide any reason to think it is unsafe.”