Researchers Seek Early Biological Changes That Could Signal Alzheimer's

Not surprisingly, most Alzheimer's disease research is focused on the late-onset form of the disease, which is the type that most people with Alzheimer's have. However, a new study targets the early-onset type.

It will be headed by John Morris, M.D., director of the Alzheimer's Disease Research Center at Washington University in St. Louis. Collaborators are affiliated with some other American medical centers, a medical center in England, and several in Australia. The study will be funded by the National Institute on Aging (NIA) and will last six years.

The early-onset type of Alzheimer's, which can afflict people as early as their 30s or 40s, is rare and due to a mutation in one of three different genes—amyloid precursor protein, presenilin 1, and presenilin 2. It is passed on from one generation to the next like Huntington's disease, that is, as a dominant mutation. So any person who has one of these mutations will get Alzheimer's.

Thus Morris and his team are seeking 300 volunteers who have a biological parent with one of the known gene mutations responsible for early Alzheimer's to participate in their study. Since each mutation is transmitted by only one parent, each volunteer has a 50 percent chance of having it and thus getting Alzheimer's.

Subjects will first undergo genetic analysis to determine whether they carry one of the mutations known to cause early-onset Alzheimer's. They will then undergo, on a periodic basis, blood tests, cerebral spinal fluid tests, neuroimaging, and cognitive testing. This way the researchers can compare findings for subjects who carry one of the mutations with findings for subjects who do not. This way, they hope, they will be able to identify some of the earliest biological changes that herald early-onset Alzheimer's.

“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,” NIA Director Richard Hodes, M.D., said in a press statement. “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.”

More information about the Dominantly Inherited Alzheimer's Disease Network (DIAN) study, is posted at<www.dian-info.org>.▪