Having a gene called the APOE e4 gene increases your risk for Alzheimer's disease; you’ve been hearing about this for years.
And now Spanish researchers, in conjunction with American scientists, say a new analysis of the health records of more than 13,000 people shows that if you have TWO copies of the APOE e4 gene, you’ll almost certainly develop Alzheimer’s.
That’s not all; you’ll start having memory problems in your 60s. Which would mean that you’ll have the disease at a much younger age than most other Alzheimer’s victims.
This is certainly not good news, but all’s not lost either…
New Insights Into Genes Influencing Alzheimer’s Disease
The gene that the Spanish study focused on is known as apolipoprotein E (APOE). In 1993 researchers at Duke discovered its link to Alzheimer’s. Since then, we’ve learned a lot more about the gene.
First, everyone usually has two copies of the APOE gene – one from their mother and one from their father. The APOE gene generally comes in three varieties:[1]
- APOE e3 – This is the most common form of the gene. It has not been found to affect the risk of developing Alzheimer’s. About 75 percent of us have one copy of this gene and 50 percent of us have two.
- APOE e2 – This version of APOE is believed to provide some measure of protection against Alzheimer’s. And if someone with this variety pf APOE gets Alzheimer’s, they usually develop the disease at a later age than other folks. About five to ten percent of us have this form of the gene.[2]
- APOE e4 – This gene is the one that significantly raises your risk of Alzheimer’s. When you have two copies of this form, say the Spanish researchers, you almost inevitably will get early onset Alzheimer’s – which starts to seriously degrade your memory in your 60s. If you only have one copy, it still increases your risk but not as drastically. About 15 to 25 percent of us have one copy, and two to five percent of us have two copies.
So, this news begs the question…
Is APOE E4 a Gene of Doom For Your Brain?
The scientists who conducted this recent study report that in their study, more than 95 percent of the folks who had two copies of the APOE e4 gene had biomarkers of Alzheimer’s disease by their mid-fifties. Then, by their mid-sixties, many of these same people had started showing signs of memory and cognitive problems -- which is a younger age than most people who develop Alzheimer’s.
However, other researchers argue that the situation is not that cut and dry. They point out that people of different ethnic backgrounds probably have been shown to have different risks from these genes. For instance, a study at Stanford and other institutions found that white people who have two copies of APOE e4 have about 13 times the risk of Alzheimer’s than other white people who have two of APOE e3. And in that same study, having two copies of APOE e4 raised the risk by 6.5 times among black people.[4]
So, should you test your genes to see your risk?
According to Michael Greicus M.D. MPH, who was involved in the Stanford research, none of these studies mean that all of us should run out and get our APOE e4 status checked. “My recommendation is if you don’t have symptoms, you should definitely not figure out your APOE status. It will only cause grief at this point.”
We couldn’t agree more. And there is some good news…
Whether you’re at high genetic risk for Alzheimer’s disease or not, you have more control over whether you’ll one day develop the disease than you realize. It all comes down to your daily life choices.
Lead an Anti-Alzheimer’s Lifestyle
Research into how daily habits affect your risk for Alzheimer’s and other dementias has produced some pretty clear evidence about what you should be doing to protect yourself. For instance, research summed up by the National Institutes on Aging shows that you should get a couple of hours or so of moderate to vigorous exercise every week, don’t smoke, go easy on alcoholic drinks (or don’t drink at all), keep your mind active with mental activity, don’t skimp on sleep and eat a Mediterranean style of diet that includes plenty of fresh fruits and vegetables. Plus, you should stay socially engaged with friends and family.[5]
And by the way, some of the studies on lifestyle and Alzheimer’s risk have included people with the APOE4 gene, and despite this, they too have achieved a dramatic reduction in risk for the disease.
The fact of the matter is your lifestyle is still your best bet for keeping your Alzheimer’s risk low. Smart lifestyle choices also help to keep your heart healthy, too. That’s true no matter what your genetics turn out to be.
- Mayo Clinic Staff, “Alzheimer's Genes, Are You at Risk?” https://www.mayoclinic.org/diseases-conditions/alzheimers-disease/in-depth/alzheimers-genes/art-20046552
- National Institute on Aging. “Alzheimer's Disease Genetics Fact Sheet,” https://www.nia.nih.gov/health/genetics-and-family-history/alzheimers-disease-genetics-fact-sheet
- Fortea J, et al. “APOE4 homozygozity represents a distinct genetic form of Alzheimer's disease” Nat Med 2024 May 6. doi: 10.1038/s41591-024-02931-w https://pubmed.ncbi.nlm.nih.gov/38710950/
- Belloy ME, et al. “APOE Genotype and Alzheimer Disease Risk Across Age, Sex, and Population Ancestry” 2023 Dec 1;80(12):1284-1294, https://pubmed.ncbi.nlm.nih.gov/37930705/
- National Institutes of Health, “Combination of healthy lifestyle traits may substantially reduce Alzheimer’s” https://www.nih.gov/news-events/news-releases/combination-healthy-lifestyle-traits-may-substantially-reduce-alzheimers