World Alzheimer’s Day

In honor of World Alzheimer’s Day, we’re linking to a few posts and stories about the disease. Alzheimer’s disease is the most common form of dementia and affects more than 35 million people worldwide.

23andMe first began allowing customers to learn about their genetic risk for late-onset Alzheimer’s disease a little more than a year ago. We report on variants of the APOE gene (e2, e3, and e4) and provide a risk estimate for the disease for customers with European ancestry. The 23andMe report also includes detailed background information on Alzheimer’s including other known risk factors for the disease, such as obesity and high cholesterol.

Although some are critical of giving people access to this information, many people say that despite their fear of Alzheimer’s they would rather know their risk than remain in the dark about the danger. For some knowing their APOE status and Alzheimer’s risk may encourage them to engage in activities to stave off the disease, or prompt them to participate in clinical research that could lead to more information about the causes and possible cures for Alzheimer’s.

Recently, scientists discovered a rare genetic variant that may be protective against the disease. In people of Icelandic descent, the T version of the variant (also known as the A673T variant in the APP gene) was associated with about five times lower odds of Alzheimer’s. This finding was first reported in the journal Nature over the summer.