Gene drive: bad news for invasive rodents…

by Ralf Stutzki, March 1, 2017

The MIT Technology Review recently published an article about what US conservation groups claim to have established for the first time: an evolution-warping technology in mammals called „gene drive“. In biasing the inheritance of DNA this transformative technology promises to become an effective tool for synthetic species conservation: invasive rodents (particularly rats and mice), which immigrated oceanic islands by ship and shipwrecks, have become significant troublemakers imperilling e.g. native sea birds.

While the Santa Cruz based conservation group Island Conservation in the past has underscored its motto „preventing extension“ particularly by bombing (!) small islands with rat poison, „gene drive“ may become an even more effective tool in the future - particularly for more populated and larger areas. Hence the non-profit is working on engineering „daughterless“ mice which - having received gender-biasing effects with the help of a gene drive - will ideally lead to a male-only offspring. This, it is expected, will minimize the mouse population on an island immensely; possibly bring it even down to zero. Currently two research teams at University of Adelaide and Texas A&M University are working on the male-only mouse line, using CRISPR (Adelaide) and harnessing naturally occurring genetic elements (A&M). The first-generation has been engineered and is currently being bred in order to study the effects on, and performance of, future generations. If everything works out well a huge market is waiting to be harvested: just last year New Zealand’s government announced its ambitious „Predator Free 2050“ plan, which aims at killing every possum, rat and weasel in its territory; and Island Conversation already thinks about implementing this new engineering technology on mainland areas such as slums.

In my opinion saving seabirds from mice and rats by means of transformation technologies is an appealing idea. After all, the birds were there first. And they seem to be the nicer animals anyhow. Gene drive already sounds like a better alternative to using poison, which leads rodents to bleed to death after they eat it. Furthermore, it is rather difficult to convince other animals not to eat poisoned prey and suffer the same fate. There are many good arguments in favour of introducing this new engineering tool; and there are many good arguments against it. Ethics can cover both sides. But prior to weighing pros and cons of introducing new engineering technologies, I believe we first need a discussion about cause and effects, about human nature and the moral value 'responsibility'. In our case we are not merely focussing on saving seabirds threatened by mammals on some far away islands. What we need is a change of perspectives: the island is here – and so is the root of the problem. Things have not changed since the old days in this respect. The invasive mammals really weren’t invaders in the first place – man brought them there, unintentionally, perhaps, but still. And man most likely did not foresee all the consequences his extensive pioneering travels and expeditions would cause in the long run. Still – man is the cause of a problem which he now – generations later – attempts to solve with new engineering technologies.

Consequentialist ethics schools for more than two hundred years have argued that responsible ethics is primarily a matter of weighing and calculating the effects of a deed and that future consequences must be included in our „moral math“ as much as possible. This is a great concept indeed, despite the fact that it simply does not really work that well – ask the seabirds. As is the case with numerous scientific endeavours trying to set off heroic paradigm changes for the improvement of the human (or for that matter whichever) condition – there always remains an area of the unforeseen and unpredicted, the consequences of which may turn our scientific well intended pioneering project into mildly spoken something less than an advancement.

This is why I believe „gene drive“ is also a reminder to the scientific community that the issue of responsibility – more than anything else – needs to be a core value to any research project setting out for new frontiers. This particularly holds true for our NCCR Molecular Systems Engineering too, where the issue of responsibility needs to be discussed in light of its possible future outcome (good or bad).

There are, of course, a number of other highly controversial issues gene drive technology raises and which the MIT Technology Review addresses. Unfortunately they cannot be discussed here. But if you are interested – read the article. I find it highly recommendable.

Ralf Stutzki

Ralf Stutzki, Head Ethics