CHICAGO -- Studying DNA from more than 1.5 million people, an international team of researchers has identified points of DNA that increase the risk of cardiovascular disease and also heighten the risk for Alzheimer's disease.
The researchers, from Washington University School of Medicine in St. Louis and the University of California in San Francisco, looked at the differences in the DNA of people with factors that contribute to heart disease or Alzheimer's disease and identified 90 points across the genome that were associated with risk for both diseases.
Their analysis confirmed that six of the 90 regions had very strong effects on Alzheimer's and heightened blood lipid levels, including several within genes that had not previously been linked to dementia risk. These included several points within the CELF1/MTCH2/SPI1 region on chromosome 11 that previously had been linked to the immune system.
The researchers confirmed their most promising findings in a large genetic study of healthy adults by showing that these same risk factors were more common in people with a family history of Alzheimer's, even though they had not themselves developed dementia or other symptoms such as memory loss.
They focused on specific risk factors for heart disease, such as a high body mass index, type 2 diabetes and elevated triglyceride and cholesterol levels (HDL, LDL, and total cholesterol), to see if any of these well-recognized risk factors for heart disease also were genetically related to Alzheimer's risk.
"The genes that influenced lipid metabolism were the ones that also were related to Alzheimer's disease risk," said Celeste M. Karch, an assistant professor of psychiatry at Washington University School of Medicine. "These findings represent an opportunity to consider repurposing drugs that target pathways involved in lipid metabolism."
Although more research is needed, the new findings suggest that if the right genes and proteins could be targeted, it may be possible to lower the risk for Alzheimer's disease in some people by managing their cholesterol and triglycerides.
This is the largest genetic study of Alzheimer's disease.
The study is scheduled to be published on Nov. 12 in the journal Acta Neuropathologica. (Xinhuanet)