A 16-cell embryo on the head of a pin. Dr Yorgos Nikas/Science Photo Library
The single most controversial development in biology in 2015 is a relatively cheap, easily manipulated technology for modifying the human genome.
Called Crispr, this tool allows scientists to “edit” the genome by deleting or adding DNA sequences. In just a couple of years, frenetic activity in labs around the world has taught scientists how to target and activate or silence specific genes. The implications for plant, animal and human biology are immense. For humans, Crispr opens up an panorama of dramatic cures and even enhancing the human genome.
But it is also quite troubling. Gene editing with Crispr only got started in 2013, but within two years position papers on ethical issues were already starting to flow.
Tinkering with the human germline has been off-limits for decades even if the mind-boggling experiments basically took place in the realm of science fiction. Since the 1970s there has been a consensus that scientists should not “play God” by creating “designer babies”. This was been codified in UNESCO’s 1997 Universal Declaration on the Human Genome and Human Rights, which implies that germ-line interventions “could be contrary to human dignity”. Why? Because “the human genome underlies the fundamental unity of all members of the human family, as well as the recognition of their inherent dignity and diversity.” It almost possesses a sacred character: “In a symbolic sense,” the Declaration states, “it is the heritage of humanity”.
However, as has happened many times before, the scientific consensus on what was impossible started to break up as soon as it became possible.
In March two statements appeared in the world’s leading science journals. In Nature, Edward Lanphier, a leading figure in Crispr-related research, and four colleagues, called for a voluntary moratorium on modifying the genome of eggs, sperm or embryos. They opposed “germline modification on the grounds that permitting even unambiguously therapeutic interventions could start us down a path towards non-therapeutic genetic enhancement”. In other words, we might move towards a society of do-it-yourself eugenics in which parents could buy genetic cassettes for their embryos to make them run faster, have a higher IQ, or have blue eyes.
A statement in Science by experts in Crispr, establishment scientists and bioethicists was more accommodating. They only urged that germline modification be “strongly discouraged”, “even in those countries with lax jurisdictions”.
Guess what? A month ago, scientists in a country with a lax jurisdiction, China, announced that they had used Crispr technology to genetically engineer human embryos. Researchers at Sun Yat-sen University, in Guangzhou, obtained defective human embryos from an IVF fertility clinic and targeted a gene which can cause beta thalassemia, a serious blood disorder.
From a technical point of view, the results were disappointing. The researchers injected 86 embryos and examined them after 48 hours when they had grown to 8 cells. Of these, 71 survived, and 54 were analysed. Only 28 had successfully spliced the target gene, and only a fraction of these contained the correct replacement gene. They also found that there were a number of “off-target” mutations somehow caused by Crispr.
Had these been viable embryos, Crispr would have caused much more illness than it cured.
Notwithstanding these dismal results, some scientists are bound to press on in the hope of improving the technique. In China, research will proceed willy-nilly because there is little ethical oversight. In the United States and Britain, scientists will have to wait for government approval.
A fascinating ethical gap is opening up between the two countries. The director of the US National Institutes of Health (NIH), Francis S. Collins, has declared forthrightly that the NIH would not fund this kind of research. He cited “the serious and unquantifiable safety issues, ethical issues presented by altering the germline in a way that affects the next generation without their consent, and a current lack of compelling medical applications”.
But in Britain, it was hard to find scientists or bioethicists who were opposed, let alone alarmed, by the news. “It’s no worse than what happens in IVF all the time, which is that non-viable embryos are discarded,” said bioethicist John Harris. “I don’t see any justification for a moratorium on research.” And Oxford bioethicist Julian Savulescu, the editor of the Journal of Medical Ethics, even declared that Crispr research on human embryos is “ethically imperative”.
One of the UK’s leading stem cell researchers, Robin Lovell-Badge, was almost enthusiastic. “I disagree with a moratorium, which is in any case unlikely to work well,” he said. “Indeed I am fully supportive of research being carried out on early human embryos in vitro, especially on embryos that are not required for reproduction and would otherwise be discarded.”
It’s déjà vu for observers of bioethical trends. The debate over Crispr is unfolding exactly as the debate over human embryonic stem cells did. Scientists are excited by a revolutionary technology which has the potential to cure genetic diseases, aid the discovery of new drugs and promote greater understanding of genetics. Yet some of its applications cross a bright ethical line. With stem cells, it was mass destruction of human embryos. Crispr can also involve destroying embryos, but even more importantly, it is a tool for eugenics.
In the US, government officials are cautious because they know that this could easily become a political firestorm. However, the only real threat they can make is withholding Federal funding. In the meantime, privately funded research will continue. In the UK, the government and the scientific establishment will attempt to manufacture a new consensus by overwhelming the public and politicians with a tsunami of green papers, white papers, public consultations, Parliamentary inquiries and public relations. Their aim will be to pass new legislation enabling eugenic experiments under close government scrutiny — paid out of the public purse.
Like all technology, Crispr is neither good nor bad in itself. It could be immensely helpful in medicine, agriculture, drug discovery and many other areas. But unfortunately, many scientists are jumping on the eugenics bandwagon. The bitter debate over human embryonic stem cells went on for years. Crispr is sure to throw petrol on the bonfire all over again. Be prepared.
Michael Cook is editor of MercatorNet.