Inherited Risk for Alzheimer's Disease: APOE ('APOE test')
Alzheimer's Disease Gene APOE
Your APOE genotype is reported either e22, e23, e33, e24, e34, or e44, along with information on relative risk for AD.
This is not a diagnostic test and does not indicate the presence or absence of Alzheimer's Disease. APOE genotype is not an absolute indicator that a person will or will not develop AD.
NPI 1467 7837 53
The e4 form of APOE multiples risks of memory impairment, cognitive decline & Alzheimer's disease
One in five women, and one in 10 men, develops Alzheimer's disease by age 85. It is caused by many factors, both inherited and related to lifestyle. Memory impairment and cognitive decline share risk factors with Alzheimer's disease.
The APOE gene has three forms called e2, e3, and e4. Our test evaluates two locations in the gene (rs429358 (T>C) + rs7412 (T>C)) in order to distinquish e2, e3 and e4.
You have inherited two copies of APOE, one from each parent, your genotype. Most people inherit the e33 genotype (average risk); e34 & e24 have 3-fold higher risk; e44 has 8-fold higher risk; the e23 genotype has 2-fold lower risk.
This information defines a 16-fold range of risk. A wider range of risk is defined by the AD Gene-Gene Panel that evaluates APOE and genes involved in inflammation and cholesterol metabolism.
No claim is made that all genes relevant to Alzheimer's disease, cognitive decline, or memory impairment are tested. Further, carrying the lower risk combination e23 does not guarantee that you will not develop these conditions, nor does carrying e34 or e44 guarantee that you will develop these conditions. We hope that you share this information with you physician, who is welcome to contact us.
Alzheimer's Disease Links
- Corder EH., Saunders AM, Strittmatter WJ, Schmechel DE, Gaskell PC, Small GW, Roses AD, Haines JL, Pericak-Vance MA. Gene dose of apolipoprotein E type 4 allele and the risk of Alzheimer's disease in late onset families. Science. 1993 Aug 13;261(5123):921-3.
- Corder EH, Saunders AM, Risch NJ, Strittmatter WJ, Schmechel DE, Gaskell PC JR, Rimmler JB, Locke PA, Conneally PM, Schmader KE et al. Protective effect of apolipoprotein E type 2 allele for late onset Alzheimer disease. Nat Genet. 1994 Jun;7(2):180-4.
- Casseli RJ, Dueck AC, Osborne D et al. Longitudinal modeling of age-related memory decline and the APOE e4 effect. N Eng J Med 361:255-263, 2009.
- Christensen H, Batterham PJ, Mackinnon AJ et al. The association of APOE genotype and cognitive decline in interaction with risk factors in a 65-69 year old community sample. BMC Geriatrics 2008;8-14