Gene-tinkering by amateurs could lead to disaster: study

30 Sep 2016

The simplicity and low cost of tools to edit the genetic code means ''garage scientists'' - or amateurs with some skill - can now perform their own experiments, posing a potential risk from the release of GM bugs, a new report suggests.

In a report published on Friday, the Nuffield Council on Bioethics said that the rise in precision ''gene editing'' tools had revolutionised biomedical research over the past ten years and could potentially have a dramatic impact on human society.

But it found that the materials needed to perform basic experiments were available to enthusiasts outside academia and established labs. This year, one firm began to sell a kit for £100 to DIY biology interest groups that allowed them to render the common soil microbe, E coli, resistant to the antibiotic streptomycin.

The report goes on to say that genetic technology has become so powerful that nations need to decide whether or not doctors should ever be allowed to modify the human species.

While the creation of GM humans is not on the horizon yet, the risks and benefits of modifying a person's genome - and having those changes pass on to future generations - are so complex that they demand urgent ethical scrutiny, the review found.

''This could transform our range of expectations and ambitions about how humans control our world,'' said Andrew Greenfield, a geneticist and chair of the Nuffield Council's working group. ''Although most uses so far have been in research, the potential applications seem to be almost unlimited.''

Genome editing has become a common tool in laboratories around the world. The most common technique, called Crispr-cas9, works like a pair of molecular scissors. It is essentially a pair of enzymes that can be designed to find and remove a specific strand of DNA inside a cell, and then replace it with a new piece of genetic material. The procedure can be used to rewrite single letters of genetic code and even whole genes.

The report found that gene editing could potentially block the inheritance of cystic fibrosis and more than 4,000 other known conditions caused by single faulty genes. But the technique may also drive profound changes in farming, the report found, where the possibilities range from swine fever-resistant pigs, chickens that only give birth to females, and hornless cows that could be housed in smaller spaces. Because Crispr-cas9 does not leave any traces, meat and other products from GM animals could find its way to market without being labelled.

Meanwhile, the simplicity and low cost of Crispr-cas9 means amateurs in the home can now perform their own experiments.

Altering the genetic makeup of a human embryo and transplanting it into a woman is banned in Britain, but there are ethical arguments in favour of the procedure, such as preventing children from inheriting genes that cause fatal diseases. But if the procedure were allowed, some fear it could open the door to what the report calls ''consumer'' or ''liberal eugenics'' where children are modified to suit their parents' preferences.

''We've identified human reproductive applications as an area that demands urgent ethical scrutiny and we must consider carefully how to respond to this possibility now well before it becomes a practical choice,'' said Karen Yeung, a law professor at King's College London, and co-author of the report.

Scientists have already begun to edit the genes of human embryos, but only for basic research. Earlier this year, researchers in China tried to add HIV resistance to human IVF embryos, which had been donated to science when tests found them to be unviable. The experiments did not achieve their goal, but highlighted how difficult the procedure was likely to be in humans.

In 2015 another Chinese team became the first in the world to edit human embryos, when they tried, and failed, to modify a gene that causes beta-thalassaemia, a potentially fatal blood disorder. Again, the work was performed on abnormal IVF embryos donated to research.

From a purely medical standpoint, there are good reasons to correct faulty genes at the embryo stage, because the defective DNA is then erased from every cell in the body. The risk comes when the modification has unintended consequences. This could harm not only the child, but their future children, because the altered gene would be in their sperm or eggs.

In light of the report, the Nuffield Council has set up two new reviews to look specifically at the ethics of gene editing in human reproduction and livestock.

One major question will be where to draw the line on what is acceptable if gene editing is approved in humans, in principle. It may be morally acceptable to correct a faulty gene that will definitely pass on a fatal disease to a child. But what about a gene that has a chance of increasing by 10 per cent a person's risk of heart disease or Alzheimer's? The report notes that in the future, it may be possible to enhance people with genes from other organisms, for example to improve night vision and sense of smell.

''It is only right that we acknowledge where this new science may lead and explore the possible paths ahead to ensure the one on which we set out today is the right one,'' said Yeung.