Mutated gene may protect brain from Alzheimer’s

A gene mutation in Iceland may give researchers new clues on why some people develop Alzheimer’s and others don’t.

News of the discovery has the pharmaceutical research world riveted, since researchers have long recognized a link between Alzheimer’s and excessive levels of a protein-related substance called beta amyloid. Unfortunately, early efforts to produce amyloid-reduction drugs have not been considered successful.

The gene mutation, announced this week in Nature journal, causes the brain to produce much lower amounts of beta amyloid. The mutation also appears to override the effects of one of the strongest genetic risk factors for Alzheimer’s, the presence of double ApoE4 genes, the study found.

The mutation was discovered when scientists conducted genetic research on 1,795 people in Iceland and found that those who had the gene mutation were five times more likely to reach age 85 without Alzheimer’s.

Outside Scandinavia, the gene mutation is relatively uncommon, yet researchers are not sure what prevents or triggers the onset of Alzheimer’s in other regions.

About one in 100 Icelanders had the mutant gene, researchers found. By contrast, only one in 10,000 North Americans have the mutation.

In the United States, 5.4 million people live with Alzheimer's, according to the Alzheimer's Association. Patient care costs for Alzheimer's and other dementias could exceed $200 billion this year alone.

In a related story, read about an industry/academic collaborative that has formed to study the ApoE4 gene variant associated with late-onset Alzheimer's.

Topics: Alzheimer's/Dementia , Clinical