Deadly Genetic Two-fer

Same mechanism that destroys brain cells in Alzheimer's disease also implicated in Down Syndrome

(RxWiki News) The genetic mechanism that destroys brain cells responsible for Alzheimer's disease is also the cause of early development of Alzheimer's disease in people with Down Syndrome.

The finding from the University of British Columbia and Vancouver Coastal Health Research Institute may lead to a potential new target for drugs, delaying dementia onset in both groups.

Led by Dr. Weihong Song, Canada Research Chair in Alzheimer's disease and a professor of psychiatry in the UBC Faculty of Medicine, the study found that increased production of a protein (Regulator of Calcineurin 1 or RCAN1), spurs a chain of events that destroy neurons in the hippocampus and cortex in people with Down Syndrome and Alzheimer's disease.

Song said death of neurons is the foremost reason for memory loss and other cognitive impairments in Alzheimer's disease, which is also the main reason people with Down Syndrome develop dementia long before most, generally in their 30s. Neuronal death is the primary reason people with Down Syndrome have shortened life spans.

Some Alzheimer's disease patients have similarly elevated levels of the RCAN1 protein as those with Down Syndrome, despite having two copies of the responsible gene.

Now that the culprit gene and protein have been identified in this process, Song said researchers can develop therapies that interfere with the gene's ability to produce the protein.

Alzheimer's disease is the most common form of dementia in the United States, usually affecing those over age 60.

Down Syndrome is a congenital abnormality resulting in developmental delays. The average lifespan of someone with Down Syndrome  is about 49 years.

Review Date: 
January 14, 2011