Science Fact: GMO humans – that’s people, genetically modified: the latest collision of science with ethics. If you’re uneasy about eating foods that are GMO (Genetically Modified Organisms), how do you feel about people designing their next child from an online genetic catalog, then picking up the embryo at their convenience?
A baby, configured as if you were ordering a new laptop? If you find that idea distasteful, you will easily understand the firestorm of criticism that greeted the latest Chinese bio research.
GMO Humans in China
The UK Telegraph had the apt headline: China shocks world by genetically engineering human embryos. The article went on to summarize research led by Junjiu Huang at Sun Yat-sen University, in which the scientists tried to replace a defective gene in a human embryo. They used a technique known as CRISPR/Cas9, which has become recently popular for gene editing.
The researchers took steps to ward off the criticism they knew would be aimed at them:
– They worked only with tripronuclear single-cell embryos. These are eggs that received DNA from two sperm rather than one, and because of the excess genetic material they can never develop into a fetus.
– They targeted the gene that causes thalassemia, an often fatal blood disease, so they could claim the worthy goal of saving lives, as opposed to helping parents create a blue-eyed superchild.
Despite these misdirections, biogeneticists were not fooled, and recognized the work as stepping boldly over a shaky ethical line that had restrained many previous researchers. The leading journals Nature and Science refused to publish the article due to ethical concerns, and the Chinese team eventually published in the journal Protein and Cell.
GMO Humans – the Establishment Response
While the Chinese team was shopping for a receptive publication venue, news of the work percolated through the biogenetics community. A team of eighteen Nobel Laureates and other luminaries had met at Napa, California in January to discuss bioethics. The group accelerated its follow-up discussions to develop a policy statement that they published in Science magazine on April 3, just two days after the Chinese article was accepted for publication. The policy statement notes that current technology “allows any researcher with knowledge of molecular biology to modify genomes” and calls for a moratorium on creating GMO humans. They call for open discussions between scientists, attorneys, bioethicists, government agencies, interest groups and the general public to develop generally agreed guidelines on what should and should not be done.
It’s worth pointing out that the Chinese work was not that successful, at least at this early stage. The researchers treated 84 embryos, of which 71 survived; they tested 54 of the survivors. Only 28 of these had their genes successfully spliced, and only a fraction of those contained the desired gene replacement. Even worse, the gene manipulation technique led to a large number of unexpected mutations in completely unrelated genes. However, the researchers accomplished what was presumably their goal, to have the fame and notoriety of being first to charge into the DMZ of GMO humans.
Since at least four groups in China are attempting to modify genes in human embryos, we can expect additional attempts to engineer GMO humans.
Science Speculation: To me, the ethical objections to GMO humans do not draw a sharp line between good and evil – they occupy a continuum.
GMO Humans: the Slippery Slope
Ethical concerns about GMO humans may be placed along a classical “slippery slope,” leading from life-saving science to panic-inducing meddling:
– Plant breeding to improve yields and pest resistance has been going on for thousands of years. The accompanying increases in agricultural productivity have been welcomed by those concerned with global food security.
– GMO worriers think that Luther Burbank-style plant work is fine, but draw the line at high-tech breeding methods, as discussed in an earlier blog.
– Animal genetic modification hopes to conquer both human and animal diseases: insect-borne diseases; antibiotic-resistant bacteria; and honey bee colony collapse disorder; many people see this work as valuable and even necessary.
– No matter what we learn from animals, people are different; if we want to correct genes that lead to fatal diseases in humans, we need to learn what techniques work and don’t work; the level of genetic errors found by the Chinese group is frightening and would certainly need correction before anyone would try to prevent a serious disease.
– Replacing a gene that kills a person at a young age sounds worthwhile; but what about improving a gene that simply raises your risk for hypertension or obesity? Does this constitute correcting a disease, or are we instead encouraging people to have lazy health habits?
– If we change genes to combat disease and improve health, shouldn’t we also want to improve intelligence, strength and stamina?
– What if prospective parents feel that being unattractive is a crueler fate for their child than being prone to disease? Forget cosmetic surgery: it’s needlessly expensive and invasive. Just design your embryos and presto! GMO humans, perfect in every way! In a few years the streets might be teeming with celebrity look-alikes.
– The fact that GMO humans will pass their genome down to future generations causes many ethicists even more pain. The Chinese study found many unwanted and unintended genetic mutations in their work; even when gene modification becomes routine, the possibility exists that GMO humans will be carrying seriously undesirable genes, which may not become evident until generations later.
Thus we might start out trying to cure a disease, but rapidly evolve to playing God with the human species.
The Un-sapient Actions of Homo Sapiens
There have been many spectacular failures when humans have tried to improve on nature by introducing species that later became invasive. Here are a few notable examples:
– Rabbits introduced to Australia for food and hunting
– Possums introduced to New Zealand for food and fur
– Burmese pythons introduced to Florida as pets
Of course, the accidental spread of species by human carelessness or lack of awareness is even more common than intentional introduction.
Science is unfortunately amoral, lending itself to both good and evil purposes. Even the well-meaning scientists who try to guide global research along ethical pathways have almost no control over the Wild West world of biogenetics.
However: although we humans are not as smart as we think we are, we are generally smarter than we act. So I think there’s a good chance that at the intersection of economics, politics, ethics and public sentiment, new rules and norms will develop. Those may provide some guidance and restraint, even for those who have the hubris to want to create GMO humans.
GMO humans – a cause for alarm? Or is it one more technical development that will gain cautious social acceptance?
Drawing Credit: dayatbanggai, on openclipart.org