Currently, 10% of people age 65 or older have Alzheimer’s disease (AD), and the risk for Alzheimer’s disease increases considerably with age. It is a disease for which prevention needs to start decades before the symptoms appear.[ref]
One way to understand your Alzheimer’s risk – and to understand the mechanisms by which the disease occurs – is to look at genetic variants that increase the risk for Alzheimer’s. On the other hand, you can also learn a lot by looking at genetic variants that protect against Alzheimer’s.
Genes combine with environmental exposure and lifestyle to determine your risk for Alzheimer’s disease. There are genetic variants that increase your risk for Alzheimer’s disease. Other variants decrease your risk for the disease.
Even if you don’t carry the protective variants below, a lot can be gleaned from understanding how the variants work and why they decrease the risk of Alzheimer’s. This seems to be a relatively new field of research, but it is interesting to note that several of these protective genetic variants are involved in either cholesterol or lipid metabolism in the brain.
Amyloid-β is a protein formed when enzymes cut the APP (amyloid precursor protein) protein into smaller fragments. Some of the protein fragments move out of the brain. But amyloid-β that isn’t cleared can build up around neurons, forming plaque.
There are currently no medications for curing Alzheimer’s disease, and research shows that preventative actions need to start decades before the onset of the disease.
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