apolipoprotein e-4 genetic (dna) test
overview
most people who develop alzheimer's disease do not have a history of the disease in their families. but if you do have a family history of alzheimer's disease (one or more members of a family have had the disease), then your risk of getting it is higher. when a disease is found in families, the cause could be genetic (heredity), something in the environment, lifestyle choices, or a combination of these things.
a blood test can look for a substance that seems to increase a person's risk for alzheimer's disease. the gene is called apolipoprotein e-4 (apoe-4). the presence of apoe-4 cannot predict for sure whether a person will develop alzheimer's disease. many people who have the apoe-4 gene do not get alzheimer's disease, and many people who do not have the gene still develop the disease. most experts do not consider apoe-4 testing a necessary or useful part of evaluating a person with suspected alzheimer's disease.
early-onset alzheimer's
sometimes people develop alzheimer's disease at a young age, between the ages of 30 and 60. this is referred to as early-onset alzheimer's disease or autosomal dominant alzheimer's disease. it is not common (less than 5 out of 100 cases), and this form of the disease has been linked to defects in specific genes. there is a 50% risk that these genes will be passed on. a person who inherits the genetic defect will most likely develop alzheimer's disease.
credits
current as of: november 15, 2023
author: healthwise staff
clinical review board
all healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
current as of: november 15, 2023
author: healthwise staff
clinical review board
all healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
