More than 275 million completely new genetic variants have been discovered in humans, and some of them could reveal an increased risk of cancer or diabetes.
Researchers led by the National Institutes of Health (NIH) in Bethesda, Maryland, revealed the findings after studying the genomes of 245,000 Americans, about half of whom were minorities.
Most of the variants had no effect on health, the researchers said, but nearly 4 million were found in genes linked to increased risk of cancer, diabetes and heart disease, among other conditions.
Some of the variants were detected in genes related to cancer and diabetes (file image)
Dr. Josh Denny, lead author of the study, said, “Sequencing diverse populations can lead to new drug targets that are relevant to everyone.”
“It may also help uncover disparities that lead to targeted treatments for people experiencing a higher burden of disease or different diseases.”
He added: “This is huge.”
The research is part of the All of Us program, the $3.1 billion national project that aims to “close the gap” in gene research that until now has focused mainly on people of white origin.
Nearly 90 percent of genetic studies to date have been conducted in people of European ancestry, estimates suggest.
The project aims to change this by assessing the health profiles (including genetics) of one million American adults, about half of them minorities, by the end of 2026.
Dr. Alicia Martin, a population geneticist at Massachusetts General Hospital in Boston, said the project was a “huge resource, particularly for African American, Hispanic and Latin American genomes.”
“This is something that is sorely lacking in the vast majority of large-scale genomics pools and biobank resources,” he added. Nature.
The latest findings were revealed today in a package published by Nature, Communications Biology and Nature Medicine.
In one of the papers, of which nearly 40 percent of participants were minorities, researchers found 611 genetic markers that could drive diabetes progression, 145 of which had not been previously reported.
They said the new variants could help “inform diabetes care,” particularly for adults from minority backgrounds.
In another study, researchers looked at pathogenic variants, or genetic variants that increase the risk of a certain disease, such as cancer.
They found that among people of European ancestry, 2.3 percent had a pathogenic variant.
However, for comparison, among those of African descent, they said this figure fell to 1.6 percent.
“This is clearly a huge gap, because the majority of the world’s population is not of European descent,” Dr. Denny said.
Recent studies have already shown how genetic diversity can affect disease risk.
Variants in the APOL1 gene discovered in 2010 help account for 70 percent of the increased risk of chronic kidney disease and dialysis seen in people in the U.S. of sub-Saharan African ancestry.
Similarly, a class of drugs called PCSK9 inhibitors that dramatically reduce very high levels of low-density lipoproteins (LDL), the so-called bad cholesterol, were discovered by sequencing the genetic code of 5,000 people of African descent in Dallas.
Much more work is needed to understand how the new trove of genetic variants contribute to various health conditions, but scientists believe they could be used to refine the tools used to calculate a person’s disease risk.