How common is the APOE4 gene?
In the US, an estimated 20 to 30 in 100 people carry APOE4 and about 2 in 100 carry two copies. Frequency differs by ancestry. Here are the sources.
Key takeaways · TL;DR
In the US, an estimated 20 to 30 in 100 people carry APOE4 and about 2 in 100 carry two copies. Frequency differs by ancestry. Here are the sources.
By Dr. Kevin Tran, Doctor of Pharmacy · Last updated: October 24, 2026
In the United States, an estimated 20 to 30 in 100 people carry one or two copies of APOE4, and about 2 in 100 carry two (Alzheimer's Association). Frequency differs by ancestry and region. APOE4 is common, not rare, and carrying it raises the chance of Alzheimer's without deciding it.
The numbers
Everyone has two copies of APOE, one from each parent. The gene has three common versions: APOE2, APOE3 and APOE4. "How common" can be counted in people or in gene copies. The figures below count people.
What is counted | Figure | Source |
|---|---|---|
People in the United States with one or two copies | An estimated 20 to 30 in 100 | Alzheimer's Association |
People in the United States with two copies | About 2 in 100 | Alzheimer's Association |
Most common version | APOE3, found in more than half of people | MedlinePlus |
The first row is a range because it depends on the group counted. A large minority of people carry at least one copy, and a small share carry two. These are United States figures. This post gives no worldwide figure, because no single source that Phoenix opened measures it directly.
It differs by ancestry
APOE4 is not equally common everywhere. A study of how the APOE4 version is spread across the world found that its frequency follows latitude in a curved pattern, lowest in the middle latitudes and higher toward both high and low latitudes (Eisenberg, 2010). So where your family comes from can shape how likely you are to carry it.
Ancestry also changes what carrying it means. In a JAMA Neurology analysis of about 68,000 people from East Asian, Hispanic, non-Hispanic Black and non-Hispanic White groups, the link between APOE4 and Alzheimer's varied in strength by ancestry (Belloy, 2023).
This post gives no carrier share per ancestry, because the studies above do not report a single comparable table. For one population, look for a study of that population.
How Phoenix compares
In the United States, about 2 in 100 people have two copies (Alzheimer's Association). In Phoenix it is far higher: among members with a known genotype, half carry two copies (Phoenix guide). Phoenix is a community of 750+ APOE4 carriers. This is a snapshot of who joins Phoenix, not a measure of how common anything is in the wider world.
Common does not mean certain
A common gene version is a risk factor, not a diagnosis. In one modeling study of people of European ancestry, using incidence rates from Rochester, USA, the estimated chance of Alzheimer's by age 85 was 11 to 14 in 100 without regard to APOE genotype, 23 to 30 in 100 for people with the APOE3/4 genotype, and 51 to 60 in 100 for people with APOE4/4 (Genin, 2011). The ranges run from men to women. These are modeled estimates, not a prediction for any one person, and they do not cover other genotypes or ancestries. So in that model most people with APOE3/4, and 40 to 49 in 100 with APOE4/4, do not develop it by 85. See risk by age for the full table.
Not sure whether you carry it? If you already have 23andMe data, you can find your APOE genotype in your 23andMe raw data.
If you carry APOE4, you have plenty of company. Phoenix gives you the next step to take, and a community of carriers who take their brain health as seriously as you do.
Frequently asked questions
What percentage of the population has the APOE4 gene?
In the United States, an estimated 20 to 30 in 100 people have one or two copies, and about 2 in 100 have two (Alzheimer's Association). No worldwide figure is given here.
How many people have two copies of APOE4?
About 2 in 100 in the United States (Alzheimer's Association). Half of Phoenix members with a known genotype carry two copies, which is far above the US figure.
Is APOE4 a rare mutation?
No. It is a common version of the gene. APOE3 is the most common version, found in more than half of people (MedlinePlus), and APOE4 is carried by a sizeable minority.
Does everyone with APOE4 get Alzheimer's?
No. APOE4 raises the chance but does not decide it. In a model built on European-ancestry data with Rochester, USA incidence rates, the estimated chance by age 85 was 23 to 30 in 100 for APOE3/4 and 51 to 60 in 100 for APOE4/4 (Genin, 2011). Other genotypes, such as APOE2/4, are not covered here.
Is APOE4 more common in some ancestries?
Yes. Frequency varies across the world's populations (Eisenberg, 2010), and the strength of its link to Alzheimer's varies by ancestry too (Belloy, 2023).
How do I find out if I have it?
Only a genetic test can tell you. Phoenix's guide on testing and family covers the options.
Is this medical advice?
No. Phoenix educates. A genetic counselor or doctor can advise you.
Sources
If you carry APOE4, apply to join Phoenix (60-day money-back guarantee).
This is not medical advice. Phoenix educates. A genetic counselor or doctor can advise you.
Dr. Kevin Tran
Doctor of PharmacyDr. Kevin Tran is a Doctor of Pharmacy and APOE4/4 carrier dedicated to helping others with the APOE4 gene variant take proactive steps for their health. He founded The Phoenix Community to provide evidence-based resources and support for APOE4 carriers.
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