By the time they’re 40, most people with Down syndrome develop beta amyloid plaques in the brain — a key characteristic of Alzheimer’s disease. Scientists believe this is because they have an extra copy of chromosome 21, which carries an amyloid-producing gene.
Many people with Down syndrome do develop Alzheimer’s disease, but some manage to avoid the devastating neurodegenerative consequences despite having these plaques in their brains.
To learn more about the connection between Down syndrome and Alzheimer’s disease, UCI School of Medicine researchers are spearheading a major international research effort that will follow hundreds of adults with the syndrome (ages 25+) as well as their siblings over the next five years.
Understanding who is at risk
“We want to understand who’s at risk for developing the dementia of Alzheimer’s disease and at what age they might start developing this problem,” says Elizabeth Head, PhD, professor and vice chair for research in the Department of Pathology & Laboratory Medicine.
“Can we also make some predictions about how quickly the disease might progress in that person?”
Funded by a $109 million grant from the National Institutes of Health, the multisite Alzheimer’s Biomarkers Consortium — Down Syndrome (ABC-DS) study will work to identify biomarkers of Alzheimer’s disease.
The project will build on the groundbreaking work of Ira T. Lott, MD, and Eric Doran of the UCI Alzheimer’s Disease Research Center (ADRC). Part of the UCI Institute for Memory Impairments and Neurological Disorders (UCI MIND), the ADRC is one of the only centers that historically included people with Down syndrome in its studies.
Although ABC-DS study focuses on people with Down syndrome, Head believes it will have broader implications.
“The goal is to come up with a set of markers to not only diagnose or help families prepare for what’s going to happen potentially with their loved one, but also outcome measures that could be used in clinical trials,” Head says.
“When we have an idea of what drug or lifestyle modification we might want to try, we’ll know which biomarker measures will tell us if that treatment is working.”
Findings may also inform personalized treatment plans, says Mark Mapstone, PhD, chief of neuropsychology in the Department of Neurology.
“We can use biomarkers to understand the genetic background, environmental, metabolic and other physiological factors, and to help us select the right therapy at the right time for the right person,” he says.
Their research already has yielded data to suggest that lifestyle interventions such as exercise and diet may help prevent or delay the onset of Alzheimer’s disease, which currently has no cure.
Extending quality of life
“What we’re looking to do is extend meaningful quality of life,” Mapstone says. “Prevention would be a home run, but even if we can slow it down, that would be a win.”
To support the research, the UCI School of Medicine is establishing a new center for Down syndrome research that will reach out to people with the syndrome and their families, as well as train the next generation of clinicians and researchers.
“The center is going to empower us to continue this research far into the future,” Head says. “It’s been a while since we’ve had a big light-bulb moment in Alzheimer’s disease research. Hopefully the combination of all this work will kickoff that next leap.”
Learn more about the study at mind.uci.edu/adrc/about