Medical researcher Huda Zoghbi has a compelling movie clip she shows at meetings. In it, a child, her face obscured, wrings her hands again and again, her shoulders hunched in anxiety. This is the tell-tale sign of a neurological disease called Rett Syndrome, a genetic form of autism.
Another clip shows a little huddle of mice holding and twisting their small paws over and over. Their MECP2 gene has been genetically modified – it’s the same gene that causes the odd hand-wringing behaviour of people with Rett Syndrome.
I first saw those clips 20 years ago. Creating genetically modified animals to gain an understanding of human disease is far from new. Yet a recent Nature study, where monkeys were genetically engineered to alter their MECP2 genes in order to use them as models to study autism, triggered a public backlash.
Why did this particular study prompt such concern?
There are three reasons. First, the animal was a cute little macaque with big, expressive eyes. An internet video that showed the monkey desperately running around a wire cage went viral.
As primates, monkeys are very much like us. And therein lies the rub: the same things that make primates good models for human disease make us morally uneasy.
‘the same things that make primates good models […] make us morally uneasy’
If we want to find a treatment for autism, we need to experiment on a species as close to us as possible. But is it ethical to use animals when they suffer in precisely the ways humans suffer?
Second, there was criticism that the monkey model was not even particularly valuable. Autism is a disease that shows a spectrum of disorders.
But besides running in circles obsessively, the monkeys did not exhibit the most troubling aspects of the disease, such as seizures or obvious cognitive problems.
And some argued that their unusual behaviour might have had something to do with the way the monkeys had been handled as embryos when the genetic engineering had taken place.
Other critics warned that even if the genes were responsible, their effects may be different in monkeys than in humans.
Finally, some people object to any research on species that appear to have a high level of awareness.
What to make of these objections? Twenty-five years ago, I was asked by NASA to think about a similar problem. The agency wanted to learn about the physiological and cognitive effects of space travel. A group of us met to think about whether to use animals, and if so, under what circumstances.
I told the group about the Nuremberg Principles of Human Subject research. They were established after the Nazis violated every conceivable principle of ethical research. They experimented on Jews, Roma and political prisoners. They did not administer anaesthesia.
The Nuremburg Code states that before human subjects are exposed to a medical intervention of any kind, the intervention must be tested on animals.
The Code has been widely used. The reason there is antiretroviral therapy for HIV, for example, is because it was first tested in monkeys. In fact, take nearly any drug, and it was first tested in animals.
The NASA committee approved animal tests, largely because of the Code. We drew up a set of guidelines we called the Sundowner Principles. Animal research would be allowed, we decided, if it conformed to these principles:
1 – Respect for life.
2 – Societal benefit for humans or animals.
3 – Non-maleficence. (Do no harm.)
Judged by these standards, research in monkeys for autism is ethical and if we are prepared to administer drugs to treat autism spectrum disorders in children, then it is also ethically necessary.
We have a duty to explore ways to address human suffering via science and also to be good stewards of the world’s creatures, including research monkeys. It is a decent thing to feel compassion for the monkeys that live in labs (and to be fair, for the rats, mice, clawed frogs, roundworms and zebrafish).
But the second thing we should feel is gratitude, for the dedicated scientists who are asking these hard questions on our behalf.