Examining Early, Inherited Form Of Alzheimer's

Ruzanna Harutyunyan's picture

The adult children of people diagnosed with inherited Alzheimer's disease are the focus of a new study to better understand the biology of the disease. Researchers are seeking 300 volunteers with a biological parent with a known genetic mutation causing rare and typically early-onset forms of the disorder to join the Dominantly Inherited Alzheimer's Disease Network (DIAN) study, a six-year, $16 million study funded by the National Institute on Aging (NIA), part of the National Institutes of Health (NIH). The scientists hope to identify the sequence of brain changes in early-onset Alzheimer's, even before symptoms appear, and by understanding this process, to also gain insight into the more common late-onset form of the disease.

The vast majority of people with Alzheimer's have the late-onset form of the disease, in which symptoms of memory loss become evident at age 60 or older. Less than five percent are diagnosed with the inherited form of the disease, sometimes as early as their 30s or 40s. Until now, research into inherited early-onset Alzheimer's was hindered by the rarity of the condition and geographic distances between patients and research centers. DIAN is designed to overcome those challenges.


"This collaborative, international effort will link a network of research sites in the United States, England and Australia to family members of people with these rare forms of Alzheimer's," said NIA Director Richard J. Hodes, M.D. "By sharing data within the network, we hope to advance our knowledge of the brain mechanisms involved in Alzheimer's, eventually leading to targets for therapies that can delay or even prevent progress of the disease."

The study is being led by John C. Morris, M.D., director of the Alzheimer's Disease Research Center at Washington University School of Medicine in St. Louis. Research collaborators include Massachusetts General Hospital; Brigham and Women's Hospital; Brown University; Columbia University; Indiana University; the University of California, Los Angeles; the University College, London Institute of Neurology at Queen's Square and a consortium of the Universities of Melbourne and New South Wales, and Edith Cowan University in Australia.

Each study participant will undergo the same assessments, from genetic analysis to cognitive testing. Researchers will build a shared database of blood and cerebral spinal fluid samples and neuroimages, including MRI and PET amyloid images. These assessments, samples and images should enable researchers to determine the type and sequence of changes in the brain in early-onset inherited Alzheimer's.

"While three mutated genes — amyloid precursor protein (APP), presenilin 1 and presenilin 2 — are known causes of inherited early-onset Alzheimer's, DIAN researchers now hope to find the biomarkers, or indicators, that herald the disease at its earliest stages," said Marcelle Morrison-Bogorad, Ph.D., NIA Division of Neuroscience director. "By closely monitoring the biomarkers of the DIAN volunteers, both those with and those without the mutated genes, we should gain insight into the underlying pathology behind both early- and late-onset forms of the disease."