If you'd asked people a few years ago what their personality traits were decided, most wouldn't have said polygenic scores.
But given what the scientific field of genetics has evolved, the polygenic score has been hailed as the ultimate crystal ball for our height, intelligence quotient, or even the chance of winning the Chicago Marathon. Once the full genetic code from huge number of people have been available, the range of genetic variations in people with a certain condition can be compared to those without the condition. Such information can then be used to calculate a polygenic risk score.
A selling point of commercial score – think about MyOme or 23andMe – is that the customer can find out if a kid is born with a sprinter's gene to win every game of tag or race. Or else, if you are such a strong believer in genetic determinism, that would be the chance to select the embryo for a more promising offspring, or to adjust the premium for the life insurance company.
Don't get me wrong, I am not against exploring our DNA, the source code of all life. It makes sense to get a polygenic score for coronary artery disease and work out who are at an unfavorable odds of getting heart attack. They deserve better control of risk factors. That being said, don't forget what Anneke Lucassen, a professor of genomic medicine in the NHS, has mentioned about our destiny: a person's postcode at birth can potentially predict risk of future disease just as well as the genetic code. Ten years ago, a study of over 55,000 people has confirmed that even for those deemed at high genetic risk (top quintile of polygenic scores), a favorable lifestyle can offset a nearly 50% risk of coronary artery disease.
Perhaps we do ourselves a disservice by putting too much – or too rigid – emphasis on our destiny being deterimined by genes.