Ethnic diversity in genetic studies identifies more genomic regions associated with type 2 diabetes-related traits

By ensuring ethnic diversity in a large-scale genetic study, an international team of researchers, including a genetic epidemiologist from the University of Massachusetts Amherst, identified more regions of the genome that are associated with type 2 diabetes-related traits.

The results, published May 31 in Nature Genetics, expand understanding of the biological basis of type 2 diabetes and show that expanding research into various ancestors leads to better results. Ultimately, the goal is to improve patient care worldwide by identifying genetic targets for treating the chronic metabolic disorder. According to the International Diabetes Federation, more than 460 million adults worldwide are affected by type 2 diabetes and sometimes even debilitated. Approximately 1.5 million deaths were caused directly by diabetes in 2019, reports the World Health Organization.

Cassandra Spracklen, Assistant Professor of Biostatistics and Epidemiology at UMass Amherst School of Public Health and Health Sciences, is part of the international MAGIC collaboration. This group of more than 400 global academics performed the genome-wide association meta-analysis under the direction of the University of Exeter in the UK.

“Our results are important because we are moving towards using genetic scores to weigh a person’s risk of diabetes,” says Spracklen, one of the study’s lead authors.

So far, about 88% of genomic research of this type has been carried out on white European ancestors. “We know that scores developed solely in individuals of one ancestry don’t work well in people of another ancestry,” added Spracklen.

The team analyzed data from a variety of cohorts that included more than 280,000 people without diabetes. The researchers looked at glycemic traits, which are used to diagnose diabetes and monitor sugar and insulin levels in the blood.

The researchers enrolled 30 percent of the total cohort of people of East Asian, Hispanic, Afro-American, South Asian, and sub-Saharan African descent. In doing so, they discovered 24 more loci – or regions of the genome – associated with glycemic traits than if they had done the research on Europeans alone.

“Type 2 diabetes is a growing global health challenge – with most of the largest increases occurring outside of Europe,” said Inês Barroso, professor of diabetes at Exeter University who led the research. “Although there are many genetic factors common to different countries and cultures, our research shows that they differ in ways that we need to understand. It is critical to ensure that we can deliver a precise diabetes medicine approach that optimizes treatment and care. “Everyone.”

Aside from the moral arguments that research reflects world population, our work shows that this approach leads to better results. “

Ji Chen, first author, data science expert, University of Exeter

Although some loci were not discovered in all ancestors, the team found it useful to collect information about the glycemic trait in individual ancestors.

“This is important as healthcare is increasingly moving towards a more precise approach,” says Spracklen. “If we do not account for genetic variations according to ancestry, it will affect our ability to accurately diagnose diabetes.”

Source:

University of Massachusetts Amherst

Journal reference:

Chen, J., et al. (2021) The trans-ancestral genomic architecture of glycemic traits. Natural genetics. doi.org/10.1038/s41588-021-00852-9.