Previous genetic association studies involving people with European ancestry may be inaccurate

Tuesday, November 7, 2023

NIH study finds that failing to account for mixed genetic lineages could lead to inaccuracies

Researchers have found that previous studies analyzing the genomes of people with European ancestry may have reported inaccurate results by not fully accounting for population structure. By considering mixed genetic lineages, researchers at the National Human Genome Research Institute (NHGRI), part of the National Institutes of Health, demonstrated that previously inferred links between a genomic variant that helps digest lactose and traits such as a person’s height and cholesterol level may not be valid.

The study, published in Nature Communications, shows that people with European ancestry, who were previously treated as a genetically homogenous group in large-scale genetic studies, have clear evidence of mixed genetic lineages, known as admixture. As such, the results from previous genome-wide association studies that do not account for admixture in their examinations of people with European ancestry should be re-evaluated.

“By reading population genetics papers, we realized that the pattern of genetic makeup in Europe is too detailed to be viewed on a continental level,” said Daniel Shriner, Ph.D., staff scientist in the NIH Center for Research on Genomics and Global Health and senior author of the study. “What is clear based on our analysis, is when data from genetic association studies of people of European ancestry are evaluated, researchers should adjust for admixture in the population to uncover true links between genomic variants and traits.”