Chance are, you know someone who has tested for their APOE genotype. With the advent of consumer genotyping companies such as 23andme, genetic testing for Alzheimer's risk has become increasingly accessible, with the APOE4 gene variant taking center stage in the discussion. The question that many people are asking is: Should I get tested for APOE4? This article aims to provide a balanced perspective, detailing the pros and cons to help you make an informed decision.
What Is APOE4?
The APOE gene produces a protein essential for fat metabolism and is involved in brain cell repair. There are three main variants of this gene—APOE2, APOE3, and APOE4—with the APOE4 variant being strongly associated with an increased risk of developing Alzheimer's disease. While having this gene variant doesn't guarantee that you'll develop Alzheimer's, it can significantly elevate your risk. 20-25% of people have 1 copy of APOE4, conferring a 2-3X increase in Alzheimer's risk, while 2-3% of people have 2 copies, which implies an 8-10X increase in risk.
Advantages of APOE4 Testing
Empowers You to Make Informed Choices
Perhaps the most compelling reason for getting tested is the ability to make informed decisions about your health. There are specific recommendations for those carrying APOE4 such as significantly increasing DHA consumption given impaired absorption. Additionally, research suggests that APOE4 carriers get even more benefit from a range of interventions than non-carriers. In fact, some experts suggest that by applying the right interventions, you can completely mitigate the impact of having a copy of APOE4.
Opens opportunities for clinical trials and futures therapies
There is a significant research focus on APOE4 and potential pharmacological approaches to mitigating the associated risk. Testing may open up avenues for participating in such trials. Furthermore, as therapies get approved in the future for APOE4 carriers, you'll be well positioned to take advantage.
Offers Information for Family Planning
Your genetic makeup doesn't just affect you; it could also be informative for your family members. Given the heritability of the gene, knowing that you carry the APOE4 variant could give valuable insights into your relatives such as parents who may be at higher risk for developing dementia.
Drawbacks of APOE4 Testing
Carries Emotional and Psychological Weight
Although APOE4 is simply a risk factor and is far from being deterministic, finding out that you're at higher risk for Alzheimer's can be emotionally taxing. While the REVEAL study1 showed that disclosing ApoE4 status did not cause clinically significant anxiety or depression after 6 month follow up, responses are of course very individualized. Before taking the test, consider whether you're emotionally prepared for the results.
Doesn't Guarantee Prevention or Cure
At present, there is no cure for Alzheimer's. Knowing you have the APOE4 gene can offer a sense of urgency to adopt preventive measures, but it doesn't guarantee that you'll be able to ward off the disease.
Raises Ethical and Privacy Concerns
Genetic testing often brings up privacy issues. There's always the risk of data leaks or misuse by third parties, including insurance companies, even though laws exist to prevent genetic discrimination (e.g., GINA for health insurance). Be aware of these concerns when contemplating testing.
The Decision is Yours to Make
Choosing whether to undergo APOE4 testing is a deeply personal decision that should be based on multiple factors, including your emotional readiness, family history, and the current state of your cognitive health. Regardless of your decision, remember that the genetics are just one piece of a very complicated puzzle.