Genetic factor fends off Alzheimer's and Parkinson's
Source: Stanford Medicine
Source: Stanford Medicine
About one in every five people carries a version of a gene that, although largely unsung, appears to confer protection against both Alzheimer’s disease and Parkinson’s disease, Stanford Medicine investigators and their colleagues have learned. These lucky people may someday benefit all the more from a vaccine that could slow or stall the progression of these two most common neurodegenerative conditions.
An analysis of medical and genetic data from hundreds of thousands of people of diverse ancestries from several continents has revealed that carrying this gene version, or allele, reduced people’s chances of contracting either Parkinson’s or Alzheimer’s by more than 10% on average.
The evidence suggest that a protein called tau, which is notorious for aggregating in the brains of Alzheimer’s patients, may also be involved, in some mysterious way, in the development of Parkinson’s disease.
The findings and implications are described in a paper published online Aug. 29 in the Proceedings of the National Academy of Sciences. Emmanuel Mignot, MD, PhD, the Craig Reynolds Professor in Sleep Medicine and a professor of psychiatry and behavioral sciences, shares senior authorship with Michael Greicius, MD, the Iqbal Farrukh and Asad Jamal Professor and a professor of neurology and neurological sciences, and Jean-Charles Lambert, PhD, director of research for Inserm at the University of Lille in France. Lead authors are Yann Le Guen, PhD, assistant director of computational biology in Stanford Medicine’s quantitative sciences unit; Guo Luo, PhD, an instructor of sleep medicine; former postdoctoral scholar Aditya Ambati, PhD; and Vincent Damotte, PhD, a bioinformatician associated with Lambert’s group.
The protective allele identified in the study is called DR4.
“In an earlier study we’d found that carrying the DR4 allele seemed to protect against Parkinson’s disease,” Mignot said. “Now, we’ve found a similar impact of DR4 on Alzheimer’s disease.”
The Stanford Medicine team combined dozens of medical and genetic databases collected from numerous countries — in Europe, East Asia, the Middle East, and South and North America. All told, the databases included more than 100,000 people with Alzheimer’s disease and more than 40,000 with Parkinson’s disease. The scientists contrasted the incidence and age of onset of Alzheimer’s and Parkinson’s among people with DR4 versus those without it and found a roughly 10% risk reduction in those carrying DR4. Read more…