Genetic testing - Understanding the genetics of Alzheimer’s - Genetic mutations that cause Alzheimer’s disease

Understanding the genetics of Alzheimer’s Genetic mutations that cause Alzheimer’s disease A small percentage of Alzheimer’s cases — an estimated 1% or less — are caused by specific mutations in one of three genes: the gene for the amyloid precursor protein, the gene for the presenilin 1 protein or the gene for the presenilin 2 protein. [...] The e3 form is the most common, with about 60 percent of the U. [...] An estimated 20% to 30% of individuals in the United States have one or two copies of the e4 form; approximately 2 percent of the U. [...] The e4 form, however, increases the risk of developing Alzheimer’s disease and of developing it at a younger age. [...] Understanding genetic testing for Alzheimer’s disease Implications for testing For the rare families that have a known genetic mutation for Alzheimer’s, genetic testing could be helpful because it will show whether an individual family member carries the gene mutation and will almost certainly develop the disease.