In the future, it’s possible that when you go in for a physical, your doctor will, along with the usual blood pressure test and bloodwork, analyze your genome for health risks lurking in the code of your DNA.
It’s possible your genome will suggest you’re at high risk of developing heart disease. If you are, your doctor may start you on cholesterol-lowering drugs early or could also, maybe, make predictions about what other medications are most likely to work to prevent the disease.
A treatment plan like this—tailored to an individual’s genetic risk—is one of the great promises of “precision medicine.” Whether genomic analysis will ever yield enough useful results to make it possible is a subject of heated debate. If it does pan out, it could be a game changer.
Though, as it stands, the game won’t be changed for everyone: If you’re not white, this new research may fail you.
If the new age of “precision medicine” is going to be equitable, we’ll have to fix this.
There’s an important lesson in diversity and genetics lurking here too. It’s not that people of different ethnic backgrounds have wildly different biology. It’s much more subtle, and fascinating, than that. We need to explore the vast range of human genetic variation: It could end up saving us all.
This is not a hypothetical problem: Color Genomics announced that next year, it will release a risk test for heart disease. When it debuts, MIT Technology Review reports, the product will only be useful for people of white European ancestry. Though, again, many scientists think genetic risk research is too preliminary for these risk tests to be sold to any consumer. (Color is also working on expanding its tests to cover more people.)
But the reason the test won’t work for most of the world’s population is simple: Most participants in the studies that yield predictive insights—genome-wide association studies (or GWAS for short)—are of white European ancestry. In all, white people of European ancestry make up 80% of the participants in all these studies, despite only representing a fraction of the world’s population.
This is “a vast disparity, and it hasn’t been getting a whole lot better,” says Alicia Martin, a geneticist at the Broad Institute who has co-authored papers on racial disparities in genetics research.
You can see the disparity clearly in the following chart. It plots the number of individuals used in GWAS studies over time. While there’s been some progress in recent years, the participants are still overwhelmingly white—despite the fact that white Europeans represent just a fraction of the world’s population.