An essay in today’s Wall Street Journal shares research about a new tool for analyzing hundreds of thousands of small genetic differences that can predict a range of psychological attributes from birth. The author of the essay believes the tool will transform how we see ourselves, our capacities, and our problems.
As I read the essay, I couldn’t help but wonder if I would really want to know such things about myself or my children from the moment of birth.
The author notes that in the last few years we have witnessed a DNA revolution. Our ability to read the genetic blueprint of individuals and to predict, from birth, their psychological dispositions is growing by the day.
While a century of research has found that inherited DNA differences account for about 90% of the differences in people’s physical traits, such as height and eye color, we now know that DNA also accounts, on average, for about 50% of our differences in such psychological traits as personality, mental health and illness, and cognitive ability and disability.
The new tool that has enabled such breakthroughs is called SNP (single-nucleotide polymorphism) chips, which make it possible to map out hundreds of thousands of DNA differences across an individual’s genome quickly and cheaply. Summing the effects of thousands of SNPs can create powerful DNA fortunetellers. These are called polygenic scores, and they are the stuff of the coming DNA revolution in psychology.
Predicting school performance is the most powerful polygenic score reported to date in the behavioral sciences. The author notes his research team found that the polygenic score predicts 15% of the variance in nationwide tests of school performance in the compulsory subjects of English, mathematics, and science given to all U.K. students at the age of 16. In comparison, ratings of school quality explain less than 2% of the differences in children’s school performance.
Despite this, the author stresses that no specific policy implications necessarily follow from finding that inherited DNA differences are by far the most important source of individual differences in school achievement and that schools make so little difference.
Having been around schools and teachers for the past 55 years, I’d have to strongly disagree with that last statement that schools make so little difference. Being a teacher I may be a bit biased, but I have heard story after story of what a difference a teacher has made in the life of a child.
The research team also found that children with the 10% highest polygenic scores are five times more likely to go to university than children with the 10% lowest scores. Is the author suggesting that those with the lowest 10% scores should not go to college, despite all the research indicating what a difference a college education makes for the vast majority of people?
I’ve written before about the ovarian lottery, about how much the luck of birth (where we were born, to whom we were born, when we were born, etc.) determines much of our future, even though we had no control over it. My fear is that these polygenic scores would create even more of a disparity between those whom fortune has blessed versus those whom it has not. And since it appears so scientific, people will lend it more credibility.
The author tries to soften the blow associated with knowing your child’s polygenic score with this:
What if you found out that one of your children has a low polygenic score for educational attainment? It’s just a probabilistic prediction—genes are not destiny and heritability describes what is, not what could be—but it might still be hard to accept. It is important that parents are not fatalistic about their children. On the other hand, polygenic scores might help parents understand that a child’s lack of interest in higher education is not necessarily a sign of recalcitrance or laziness. Learning is more difficult and less enjoyable for some children than for others.
Again, my fear is that the parent and child may jointly decide that school is not for the child, simply because of the polygenic score. But no one said education is meant to be easy, and I’ve always felt a better sense of accomplishment when I’ve had to struggle to learn something. These polygenic scores seem to suggest denying such an opporunity to low scorers.
Research also seems to suggest that polygenic scores predict success later in life, such as mate choice, occupational status, social mobility, and even financial planning for retirement.
Based on all of the research, the author summarizes some potential benefits of polygenic scores:
- Polygenic scoring makes it possible to identify problems on the basis of underlying genetic causes rather than behavioral symptoms.
- It shifts the focus from treatment to prevention. Polygenic scores are the perfect early-warning system. The predictive power of polygenic scoring promotes interventions to prevent problems. You can know if you or your child are at risk for alcoholism, depression, or schizophrenia, or if your child is more likely to be an extrovert.
- A further benefit of polygenic scoring is self-understanding.
I guess I can only see the problems associated with using such a tool; does the prediction become the reality? What if the results indicate a child is more likely to be an introvert; would someone view that as a negative, and try and change the child to be more extroverted? Would we steer someone away from college because of a “low” polygenic score?
I vaguely recall some research study in which one group of teachers were told that their students were superior students, and the teachers treated them as such, and the students performed well. Other teachers were told that their students were just average, and they were treated as such and ended up performing as average students. In reality, students of all abilities had been randomly assigned to both types of teachers.
I can envision a future where teachers, parents, and children become their polygenic score.
And that seems quite sad, as well as a bit discriminatory.
So personally, I don’t think I’d want to know mine or my children’s polygenic score. Going through life should be an adventure full of surprises, not something that is etched in stone from the moment we are born.
*image from The Atlantic