The quiet return of eugenics

Here follows a non-exhaustive list of my genetic flaws. I am short-sighted, more so as I age. I have bunions, dodgy knees and even dodgier shoulders. I have asthma. My skin blisters easily. My hair started going grey when I was in my late teens. I have zero talent for foreign languages, running or music. I am prone to nightmares, as well as to depression and anxiety.

Relatively mild flaws, as they go. But still, these aren’t traits I’m eager to pass on. Our three-year-old already shows a tendency for nightmares that sometimes makes me wince with guilt. Not that it’s my fault, of course. We don’t get to choose which of our genes we pass on. Every conception is a roll of the dice.

But soon that will no longer be true. In fact, it’s already not quite true, at least for those who have the means and determination to load the dice. Emerging technology is about to present parents with a set of ethical questions that make the usual kinds of debates – breast milk or formula? Nanny or daycare? – seem trivial. We have always had the power (more or less) to control our children’s nurture. Before long – perhaps in just a few years – any parent who can afford to will have control over the minutest details of a child’s nature too.

The crucial change set to turn our lives upside-down is called ‘preimplantation genetic testing for polygenic disorders’ (PGT-P), hereafter ‘polygenic screening’. Testing a foetus or embryo for some conditions is now a routine part of the modern pregnancy experience. Prenatal Down’s Syndrome tests, for instance, are so widespread that in some Scandinavian countries almost 100 per cent of women choose to abort a foetus diagnosed with the condition, or – if using IVF – not implant the affected embryo.