Use of ethnically diverse cohorts in diabetes studies ‘generates better results’

Diabetes (PA Wire)
16:00pm, Mon 31 May 2021
CBAD8A00-D2B9-4E0E-ADDF-D0366C357A34 Created with sketchtool. E9A4AA46-7DC3-48B8-9CE2-D75274FB8967 Created with sketchtool. 65CCAE04-4748-4D0F-8696-A91D8EB3E7DC Created with sketchtool.

Failing to account for genetic variation according to ancestry will impact the ability to accurately diagnose diabetes, researchers have said.

Ethnic diversity in one large-scale study meant more regions of the genome linked to type 2 diabetes-related traits were identified than if the research had been conducted in Europeans alone, scientists suggested.

Experts said the findings demonstrated that expanding research into different ancestries yielded more and better results, as well as ultimately benefiting global patient care.

It is estimated that until now, nearly 87% of genomic research of this type has been conducted in Europeans.

This has meant that the way these findings are implemented may not be best applied to people with non-European ancestries, researchers said.

The international Magic collaboration, made up of more than 400 global academics, conducted a genome-wide association meta-analysis led by the University of Exeter.

They analysed data across a wide range of cohorts, including more than 280,000 people without diabetes, looking at glycaemic traits.

These are used to diagnose diabetes and monitor sugar and insulin levels in the blood.

Failing to account for genetic variation according to ancestry will impact our ability to accurately diagnose diabetes

The researchers incorporated 30% of the overall cohort with individuals of East Asian, Hispanic, African-American, South Asian and sub-Saharan African origin.

By doing this, they discovered 24 more loci – or regions of the genome – linked to glycaemic traits than if they had conducted the research in Europeans alone.

Professor Ines Barroso, of the University of Exeter, who led the research, said: “Type 2 diabetes is an increasingly huge global health challenge, with most of the biggest increases occurring outside of Europe.

“While there are a lot of shared genetic factors between different countries and cultures, our research tells us that they do differ, in ways that we need to understand.

“It’s critical to ensuring we can deliver a precision diabetes medicine approach that optimises treatment and care for everyone.”

Beyond the moral arguments for ensuring research is reflective of global populations, our work demonstrates that this approach generates better results

The researchers found that although some loci were not detected in all ancestries, they were still useful in capturing information about the glycaemic trait in that ancestry.

Co-author Cassandra Spracklen, assistant professor at the University of Massachusetts-Amherst, said: “Our findings matter because we’re moving towards using genetic scores to weigh up a person’s risk of diabetes.

“We know that scores developed exclusively in individuals of one ancestry don’t work well in people of a different ancestry.

“This is important as increasingly healthcare is moving towards a more precise approach.

“Failing to account for genetic variation according to ancestry will impact our ability to accurately diagnose diabetes.”

First author Dr Ji Chen, of the University of Exeter, said: “We discovered 24 additional regions of the genome by including cohorts which were more ethnically diverse than we would have done if we’d restricted our work to Europeans.

“Beyond the moral arguments for ensuring research is reflective of global populations, our work demonstrates that this approach generates better results.”

The study was published in Nature Genetics.

Sign up to our newsletter