BETHESDA, Md.—The National Institutes of Health (NIH) have announced a new initiative focused on the identification of biomarkers and tracking the progression of Alzheimer’s in people with Down syndrome. The initiative will be funded by the National Institute on Aging (NIA) and the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), both of which are parts of the NIH. The combined investments total an estimated $37 million over five years and will support two highly collaborative projects. The NIH Biomarkers of Alzheimer’s Disease in Adults with Down Syndrome Initiative will apply brain imaging, in addition to fluid and tissue biomarkers, in researching how Alzheimer’s spreads in these individuals.
“This is the first large-scale Alzheimer’s biomarker endeavor to focus on this high-risk group,” said Dr. Laurie Ryan, Ph.D., chief of the Dementias of Aging Branch in NIA’s Division of Neuroscience, in a press release. “Much like the long-established Alzheimer's Disease Neuroimaging Initiative, the goal of this initiative is to develop biomarker measures that signal the onset and progression of Alzheimer’s in people with Down syndrome. Hopefully, one day, we will also use these biomarkers to determine the effectiveness of promising treatments.”
The two research teams for this project will share data, standardize procedures, increase sample size and collectively analyze data that will be later made available to the research community. The teams will use biomarkers to identify and track Alzheimer's-related changes in the brain and cognition in more than 500 volunteers with Down syndrome ages 25 and older.
The teams will apply a variety of investigative measures, including: positron emission tomography (PET) scans to track levels of amyloid and glucose, MRIs of brain volume and function, levels of amyloid and tau in cerebrospinal fluid and blood, blood tests to identify biomarkers, blood tests to collect DNA for genome-wide association studies linked to risk for or protection against Alzheimer's, evaluations of medical conditions, cognitive/memory tests and PET brain scans to detect levels of tau (a first in individuals with Down syndrome).
“Over the past 30 years, the average lifespan of people with Down syndrome has doubled to 60 years—a bittersweet achievement when faced with the possibility of developing Alzheimer’s,” remarked Dr. Melissa Parisi, chief of the NICHD Intellectual and Developmental Disabilities Branch, which heads up the NIH’s Down syndrome research. “There is much to learn about Alzheimer’s in Down syndrome, and we’re hopeful that these new projects will provide some answers. One mystery we hope to solve is whether or not the disease progresses at a faster rate in this group.”
Individuals with Down syndrome are born with an extra copy of chromosome 21, and having three copies of the chromosome is a known risk factor for early-onset Alzheimer's disease. This chromosome is the site of the amyloid precursor protein gene, which plays a role in the production of the amyloid plaques that build up in the disease. A majority of adults with Down syndrome develop signs of Alzheimer's by middle age, with a high percentage developing symptoms of dementia as they reach their 70s. Many individuals with Down syndrome present with Alzheimer’s-related brain alterations in theirs 30s that can result in dementia by their 50s or 60s, but little is known about the exact path of disease progression for this demographic.
SOURCE: NIH press release