Large-scale genetic studies do not include a racially and ethnically diverse population that greatly affects global health
A large study published in Cell titled The Missing Diversity in Human Genetic Studies affirms that the majority of studies of genetic association with disease have been performed in Europeans, what has a negative effect in global health, and proposes solutions (read entire commentary VOLUME 177, ISSUE 1, P26-31, MARCH 21, 2019).
From a bioethcial point of view, we quote an article that shows why this failure affects public healh and increase global disparities. It affirms that It’s never been faster, easier, or cheaper to sequence a human genome. An individual’s entire genetic code can be unraveled in as little as an hour, allowing researchers to scour its billions of base pairs for patterns that might predict a person’s risk of developing disease. Technologically speaking, studies of human genetics remain on the cutting edge.
78 percent of data used in GWAS come from people of predominantly European descent
On the axis of diversity, however, progress is sorely lacking.
For nearly 20 years, scientists have been using genome-wide association studies, known as GWAS, to identify connections between genetic variants and disease risk. But according to a commentary published in the journal Cell, 78 percent of data used in GWAS come from people of predominantly European descent—even though they make up only 16 percent of the global population. The failure to include racially and ethnically diverse populations in genetic research both hampers our ability to understand human health and disease and exacerbates long-standing disparities in health, the authors write.
The consequences of these data discrepancies have already proven very real. Doctors have known for decades that people of African, Puerto Rican, and Mexican descent suffer unusually high rates of asthma-related deaths, but only recently learned why this might be: These groups commonly carry genetic variants that could be making them less sensitive to albuterol, a drug used in inhalers. The connection might have been obvious when looking at a pool of diverse genomic data—but over 90 percent of lung research has been done on populations of European descent.
“This [commentary] is a very important perspective, and has exactly the kind of data we need to keep pushing this conversation forward,” says Shawneequa Callier, a bioethicist who specializes in the ethics of genetics research at the George Washington University School of Medicine and Health Sciences.
There’s been progress, but it’s minimal at best
The issue isn’t a new one—and it’s true that, at one point, things were far worse. In 2009, just seven years after the publication of the first successful GWAS, a staggering 96 percent of study participants were of European ancestry. But the lion’s share of that gap has been closed by a recent increase in genetic studies of Asians, who now represent about 10 percent of GWAS subjects.
Increases in other underrepresented populations, on the other hand, remain marginal at best. To this day, individuals who identify as being of African, Hispanic, or Latinx descent make up less than four percent of people recruited into GWAS.
This European-centric skew might represent one of the biggest obstacles to the efficacy of precision medicine, wherein doctors could use each patient’s unique genetic makeup to tailor treatments and medical advice. Already, information gleaned from GWAS has yielded crucial insights into the roles genes play in a growing list of conditions, including obesity, prostate cancer, type 2 diabetes, and schizophrenia. But as things stand, it’s those with European ancestry who will benefit the most (NOVA, March 21, 2019).