Christmas Day marks the birthday of one of the most gifted human beings ever born. His brilliance was of a supernoval intensity, but he was, by all accounts, very far from pleasant company. I refer to Isaac Newton.
Would you like your next child to have the intelligence of a Newton? It may not be long before this is a consumer choice, according to an ambitious new company founded in America a few months ago. Genomic Prediction initially plans to offer people who use in-vitro fertilisation the chance to identify and avoid embryos that would be likely to develop diabetes, late-life osteoporosis, schizophrenia and dwarfism. The key is the application of smart software to gigantic databases of genomic information from the population at large so as to spot dangerous combinations of gene variants. The founders also talk of being able to predict intelligence from genes, at least to some degree.
It is of course already common practice to screen embryos for terrible diseases, but only those simply caused by single genes: cystic fibrosis, Huntington’s disease and so forth. The new idea is to extend this capability to disorders caused by the interaction of many genes, each of small effect: and that is most of them.
This is welcome and potentially ethical, but is it also, after many false starts, the beginning of the slippery slope to designer babies? No, it is not. If anything, the new knowledge will cause such a threat to dissolve.
It is true that intelligence is one of the most strongly heritable human traits, like height. In childhood, among people who get sufficient food and a reasonable education, genes account for about 40 per cent of the variation in IQ. Later in life this rises to more like 80 per cent. If this sounds puzzling, consider this friend of mine: left a bad school at 15, worked as a lorry driver for a big company, which spotted his intelligence and paid for him to attend a top university, where he got a first, rejoined the company and is now a global senior executive: his achievement at 45 better reflects his innate intelligence than his achievement at 15. As a child we don’t get to choose our environments, so clever kids often don’t get to read as many books or do as many mind-bending maths puzzles as they would like, while stupid children read more books and get more maths tutoring than they would if left to their own devices. By adulthood, we are choosing and modifying the life that suits us.
Hence it has always been possible selectively to breed for intelligence. Francis Galton in 1869 pointed out that just as it was easy to ‘obtain by careful selection a permanent breed of dogs or horses gifted with peculiar powers of running, or of doing anything else, so it would be quite practicable to produce a highly gifted race of men by judicious marriages during several consecutive generations’.
However, human beings proved surprisingly unwilling to do this, and most governments eventually gave up trying to coerce them to do it, often with horrific eugenic policies. Then along came artificial insemination and test-tube babies, and surely now we would see a rush to have bright babies, by using sperm banks of Nobel Prize winners? But we did not. People used these technologies to have their own children, not those of Newton-like sperm donors. It is curious
how wrong most experts were about where the demand for IVF would come from: mainly from infertile couples wanting their own children, not fertile people wanting other people’s.
Strange as it may seem to academics, not everybody thinks intelligence matters all that much. They would rather have good- looking or athletic or happy or kind children than super-bright ones. And healthy comes first for almost everybody, so if there is any risk of poor health as a result of selecting an embryo for intelligence, people will, and for all we know very wisely, avoid it.
That is the first reason we will not see designer-intelligence any time soon: there will be little demand, especially if the procedure carries risks. For 50 years we have fretted about designer babies every time there is a new reproductive technology: mitochondrial donation and cloning were the most recent reason for dusting off the old canard.
The second reason is that the genes involved are too numerous and too feeble to be of any practical use. For a long time there was a puzzling gap between what studies of twins and adopted children said about the heritability of intelligence (that it was high), and what genetic surveys found (next to nothing). The first genome-wide association studies — or GWAS — came up empty when looking for gene variants associated with high IQ.
That has changed, thanks to much bigger sample sizes, such as the UK Biobank, which has looked inside the genomes of half a million people of a certain age. Thus, a recent study of nearly 80,000 people, published in May, found 40 new gene variants associated with intelligence. Another study published in Nature of 1,238 extremely gifted intellectuals turned up more gene variants, including three in a gene called ADAM12.
But the more we find, the more ridiculous the idea of selecting for intelligence looks. Each variant seems to have a small effect, so you would need to fiddle with scores of genes to make a child bright, and fiddling with them might have unforeseen consequences for the health of the child. ADAM12, for example, is hard at work in every organ of the body.
As for the concern that genomic selection for intelligence, if it comes, will be available to the rich but not the poor — well, the same is true for good education. Opportunities to buy the best genes for your children will be dwarfed for decades to come by the ability of the rich to buy the best education for their children. If you must do something, do something about that instead: and preferably do so by making all education as good as the best, rather than as bad as the worst.
Finally, staring us in the face is a more obvious reason why intelligent designer babies will not happen soon and if they do, will not matter much. Individual intelligence is overrated. This is partly the well-worn argument that lots of other characteristics determine success, especially energy and diligence. We know people who are too bright to be decisive; or conversely achieve much in spite of their apparent disadvantages.
However, I mean something more than this. I mean that human achievements are always and everywhere collective. Every object and service you use is the product of different minds working together to invent or manage something that is way beyond the capacity of any individual mind. This is why central planning does not work. Ten million people eat lunch in London most days; how the heck they get what they want and when and where, given that a lot of them decide at the last minute, is baffling. Were there a London lunch commissioner to organise it, he would fail badly. Individual decisions integrated by price signals work, and work very well indeed.
And here is the key insight from evolution. Our brains grew big long, long before we achieved civilisation. We’ve had 1,200cc of intelligence for half a million years: even Neanderthals had huge brains. For 99 per cent of that time we were just another hard-pressed species, as bottle-nosed dolphins are today, and around 75,000 years ago we teeter-ed on the brink of extinction.
What changed was not some bright spark of a new gene being turned on, but that we began to exchange and specialise, to create collective intelligence, rather than rely on individual braininess. To put it another way, dozens of stupid people in a room who talk to each other will achieve far more than an equal number of clever people who don’t. The internet only underlines this point. Human intelligence is a distributed, collaborative phenomenon.