Despite dire predictions, almost nothing but good has come from genetic technology so far, and we’ve proved that we don’t slip down such slopes: we tread carefully. The current excitement is over gene editing. A precise way of doing this, called CRISPR-cas9, is all the rage among the white-coated pipette-users.
Last month, Britain’s five leading medical research bodies (one of which, I should declare, counts me as a fellow, the Academy of Medical Sciences) issued a joint statement supporting the careful use of the new technique on human cells for research and possibly therapy. They even recognised that there might one day be a justifiable demand to use the new technique on embryos in such a way that the changes would be inherited.
We have had bio-ethical worries about six times in the past four decades. First, in the mid-1970s, the discovery of how to do genetic engineering in bacteria led to agonised debates about the risks of biological warfare and accidents. Scientists themselves imposed a moratorium and held a conference to devise rules. Today the technique is routinely used, has virtually never been misused, and has saved or improved the lives of millions: diabetics, for example, use human insulin made by bacteria genetically engineered to include human genes. It turned out better than feared.
Second, in the late-1970s, the discovery of how to fertilise human eggs in test tubes led to equally agonised debates about what this might do to human reproduction — such as allowing people to seek out highly prized human specimens to father or mother their children. In fact, the technology is used not to help people have other people’s babies, but to help them have their own. It has largely cured a wretched disease — infertility — and made millions happy. It turned out better than feared.
Third, in the 1990s scientists began to modify the genes of plants. Opponents raised the prospect of horrifying risks to our food and the environment. Yet trillions of genetically modified meals have now been eaten by animals and people with zero health problems. GM crops have cut insecticide use, raised yields and delivered healthier foods. Today’s scandal is not the harm GM crops have done, but the suffering they have not been permitted to alleviate, thanks to irrational opposition. Even if you are still worried, you must concede that so far it has turned out better than feared.
Fourth, around the millennium, scientists developed techniques to clone mammals and some of us found ourselves on talk shows discussing when vain plutocrats would duplicate themselves or their pets, and at what risk to morality. In fact, cloning has proved helpful in only a very few laboratory settings, but aside from one or two pretty harmless pet-cloning episodes, has not been used at all for frivolous purposes. It turned out better than feared.
Fifth, scientists sequenced the human genome, identified disease-causing mutations and began to offer pre-implantation genetic diagnosis to avoid bringing people into the world with conditions such as cystic fibrosis or Huntington’s disease. Critics worried that people would use the technique to make designer babies who were good at the piano or maths. Yet demand for such positive selection has proved minimal, partly because identifying specific genes for specific traits is hard — and misreads the way genomes work — and partly because, again, it turns out that people want children like themselves, not paragons. Besides, good education is still a far better way of giving a child an advantage. It turned out better than feared.
Sixth, scientists discovered how to use viruses to insert new genes into living tissues to cure certain fatal diseases — so-called gene therapy. Early trials in human beings using retroviruses triggered cancer and were abandoned. But safer lentivirus gene therapy has now proved capable of saving lives, such as those of immune-deficient babies, and is being used in more than 700 different trials. It turned out better than feared.
The score so far is six-nil to the optimists, then. Diabetics, IVF children, bees in GM crops, parents who carry cystic fibrosis or Huntington’s disease, babies with severe combined immune deficiency — all have benefited. It has been feasible to use genetic techniques for biological warfare and designer babies for decades now; and it has not happened.
As the reaction to early gene therapy failures illustrate, the slopes are not slippery. We advance very carefully down them, retreating if necessary and re-evaluating the issues at every stage. People want to use these techniques to cure diseases, not to do eugenics. Genetic knowledge has not undermined morality or respect for human life. All this does not, of course, prove that future techniques will not be abused, but it must count for something.
The latest gene-editing technique is generating attention because it is so much more precise and effective than previous ways of altering genes. Its first use will probably be in gene therapy — extracting T cells from a cancer patient, editing the cells’ genes to fight the cancer and re-injecting them — but even this is a long way off. Work on germ-line genes is even further away. Some scientists are calling for a moratorium on even the experimental use of CRISPR-cas9 on embryos until we have discussed all the ethical implications.
That would be a mistake. As genetically modified plants have shown, moratoriums are blunt instruments — easy to impose and difficult to lift when it turns out they are doing more harm than good, especially in the age of social media.
Experiments produce knowledge to inform debates. A good example is the recent debate on mitochondrial donation, a technique developed in the laboratory before being licensed for use in patients, where it may soon prevent dreadful degenerative diseases. When the ethical debate on its use happened, seven years’ worth of experimental results were on hand to answer many of the questions raised. A moratorium would have meant debating in ignorance.
We should always tread carefully, but we should take comfort from the truly remarkable track record of genetic technologies in alleviating more human suffering than we dared to hope, and encouraging fewer bad outcomes than we feared.
Matt Ridley, a member of the British House of Lords, is an acclaimed author who blogs at www.rationaloptimist.com. This article was first published the Times.
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