New study reveals dementia risk unique to people with African ancestry

In the largest-ever genetic study of dementia in people of African descent, VA researchers identified several genetic risks that differ from those found in people of European descent.

Using data from the VA Million Veterans Program (MVP), the team found multiple cases in which genetic variants may increase the risk of Alzheimer’s disease and related dementias.

The survey results will be published on December 22, 2022. molecular psychiatry.

“MVP represents a great resource for examining the genetics of many diseases, including: dementiaStudy author Mark Roeg, Ph.D., a statistician at the VA Boston Health Care System and the National Center for PTSD, said: My colleagues and I are working hard to strengthen dementia research at MVP and collaborate with other large-scale Alzheimer’s and dementia research.

“These results represent a significant increase in our knowledge of the genetic makeup of dementia risk in African ancestral populations,” Roeg said.

African descent and others ethnic minority historically underrated genetic researchaccording to the research team, which is why this study represents an important milestone.

In the United States, Alzheimer’s disease affects more African Americans than people of European descent. However, most large-scale genetic studies on Alzheimer’s disease have focused on Caucasian participants. Genes associated with Alzheimer’s disease are consistent across populations, but the researchers explained in their study that certain variants may differ by ancestry. A genetic variant called APOE E4, for example, has the greatest genetic risk of Alzheimer’s disease in people of European descent. Studies have shown that the effects of APOE E4 are half that of people of African descent.

Increase representation of non-European ancestry populations Genome-wide association studies It has been identified as an important scientific and impartiality issue in genetic research. Differences in sample sizes between previous European and non-European ancestry studies may even contribute to health disparities among minority populations, according to this study.

To address this disparity, Boston VA researchers compared the genomes of more than 4,000 MVP participants of African descent who had dementia and more than 18,000 veterans who did not develop dementia. Did. The team also conducted his second analysis comparing his 7,000 black MVP participants who reported having a parent with dementia to his 56,000 other participants whose parents did not have dementia. It was conducted. This sample is more than double his size from the largest Alzheimer’s genetic study ever in individuals of African descent.

The results showed an association between dementia risk and variants in six different genes, including APOE. Many of these genes have been linked to dementia in previous genetic studies in people of European descent, but only two of them have been identified as significant risk factors in people of African descent.

Although many of the gene variants identified in this study were associated with dementia within the group, specific gene variants associated with dementia risk differed between people of African and European descent. I was. in their race.

These new findings will help fill gaps in knowledge about Alzheimer’s disease risk based on ancestry, the researchers said. It could lead to more accurate risk assessment and also reveal new molecular targets for developing drugs to treat Alzheimer’s disease.

With more than 900,000 participants to date, MVP is one of the largest genetic research programs in the world. MVP researchers collect genetic data in addition to information on health, lifestyle, and military exposure to understand how genes influence health and disease.

MVP is also one of the most diverse genetic programs in the world. Over 150,000 African-American veterans have volunteered to participate in MVP, making him 18% of all participants. This means that the MVPs include more Africans. ancestor Thanks to its diversity and the altruism of participating veterans more than any other biobank in the world, MVP is working to bridge the racial gap in the link between genetics and disease.

“As one of the world’s largest genetic databases, MVP’s sheer scale means we can really push what we’re known for. gene “Working on the MVP data is an exciting opportunity for a researcher like me, and I am grateful to all the veterans who agreed to participate in this study,” said Roeg.

Courtesy of Veterans Affairs Research Communications