Alzheimer’s Disease Genetics
FACT SHEET
Scientists don’t yet fully understand what causes Alzheimer’s disease. However, the more they learn about this devastating disease, the more they realize that genes* play an important role in its development. Research conducted and funded by the National Institute on Aging (NIA) at the National Institutes of Health and others is advancing the field of Alzheimer’s disease genetics.
The Genetics of Disease
Some diseases are caused by a genetic mutation, or permanent change in one or more specific genes. If a person inherits from a parent a genetic mutation that causes a certain disease, then he or she will usually get the disease. Sickle cell anemia, cystic fibrosis, and early-onset familial Alzheimer’s disease are examples of inherited genetic disorders. In other diseases, a genetic variant may occur. This change in a gene can sometimes cause a disease directly. More often, it acts to increase or decrease a person’s risk of developing a disease or condition. When a genetic variant increases disease risk but does not directly cause a disease, it is called a genetic risk factor.