Headline: Big Tongues and Extra Vertebrae: The Unintended Consequences of Animal Gene Editing: Unintended consequences have included enlarged rabbit tongues and extra pig vertebrae, as bioethicists warn of hubris
Scientists around the world are editing the genes of livestock to create meatier pigs, cashmere goats with longer hair and cold-weather cows that can thrive in the tropics…
When Chinese researchers deleted a gene that limits muscle growth in mammals so that rabbits would grow leaner, their creations exhibited an unusual characteristic: enlarged tongues. Similar experiments on Chinese pigs led some to develop an additional vertebrae. Gene-edited calves died prematurely in Brazil and New Zealand…
“Humans have a very long history of messing around in nature with all kinds of unintended consequences,” said Lisa Moses, an animal bioethicist at Harvard Medical School’s Center for Bioethics. “It’s really hubris of us to assume that we know what we’re doing and that we can predict what kinds of bad things can happen.”
The belief has spread that scientists know how gene editing works “all the time, under all conditions,” says Odd-Gunnar Wikmark, a researcher at the Norway-based foundation GenOk, which studies the consequences of genetic engineering. “We of course do not.”
Critics say that editing animal DNA could introduce unwanted mutations that pose a threat to human health when consumed, and they fear that mutated genes may spread unchecked as animals breed. Proponents say they are engineering mutations just as traditional crossbreeding does, only faster.
Both the critics and proponents are right. GMOs could cause dangers and engineered beasties are faster to produce than regular breeding. Regular breeding cannot, of course, produce animals that cannot be produced naturally, whereas gene-editing can.
Just as obviously, single or few genes that are thought to control a physical attribute (like muscle) are easier to manipulate than genes thought to regulate, or moderate, behavior. But, as is clear from the examples above, even simple edits can cause freaks. Which is to say, can cause unanticipated or undesired consequences.
And they are unanticipated for the reasons quoted: scientists are too sure of themselves.
Much of the evidence in genetics about outcomes is statistical. A great deal of that is based on wee p-values, so of course it is suspect. Many false beliefs are thus entertained because a wee p screamed “Look at me! Look at me!” Exaggerations, which come free with p-values, are believed as truths.
This is not a huge big important deal when playing around with mice or flies or sheep. If an experiment goes wrong making a new pig, why, a quick trip to the bacon factory solves the problem. But inadvertently make a new mutant baby, as that Chinese scientist is alleged to have done? Well, you can go the Belgian way and kill it (using the euphemism “euthanize it”), but that destroys the souls of the baby and the killer.
It should go without saying, but I’ll say it anyway, that interactions between genes and genes and environment are not well understood—and that’s putting it nicely (I’m such a sweet man). This is particularly so in claims of genes and human behavior. We hear things like “Investigating the genetic basis of altruism: the role of the COMT Val158Met polymorphism.” Now that is hubris to the ninety-fifth degree. As if a complicated behavior like altruism—which I bet if you were pressed, right now, could not define unambiguously—can be “explained” by a polymorphism. Here’s a SNP (that’s a joke, son) from the Abstract:
Findings from twin studies yield heritability estimates of 0.50 for prosocial behaviours like empathy, cooperativeness and altruism….Altruism was assessed by the amount of money donated to a poor child in a developing country, after having earned money by participating in two straining computer experiments. Construct validity of the experimental data was given: the highest correlation between the amount of donations and personality was observed for cooperativeness (r?=?0.32, P?≤?0.001).
Heritability sounds scientific, and that “0.50” makes it seem the science was measured precisely. But as the rest of the abstract proves what we have are cheesy linear correlations based on quantifying questionnaires, all certified by wee p-values. That’s not hard science, but soft guessing.
At least they gave a definition of altruism: the amount of fictional non-money given to fictional non-existent non-poor children in fictional non-existent non-developing countries in some simple computer game. This may not be what you thought altruism was when I asked you to think of it above. But it is a definition. The hubris comes in when assuming this odd definition of altruism maps to the true definition with only negligible or non-interesting differences.
Just wait until rich parents of designer babies sue to get their money back when they discover their test-tube precious with its hand-picked COMT allele did not “cure” the hyperactivity of the child.