How to find your APOE status in your 23andMe or AncestryDNA raw data

If you have already spit in a tube for ancestry, your APOE answer may be sitting in your raw data right now, and you can read it yourself in a few minutes. It comes down to looking up two specific spots in your DNA and matching them to a table. Before you do, read the next section, because whether to look is a real decision, and reading the result correctly takes a little care.

Read this before you look

Three things to sit with first.

• You cannot unknow it. APOE status can shape how you think about your future, your family, and things like long-term-care planning. Some people are glad they looked; some wish they had not. There is no wrong answer, but be honest with yourself about why you want to know and how you tend to handle uncertain news. A genetic counselor can help you think it through, before or after.
• It is a risk factor, not a diagnosis. APOE4 raises the odds of Alzheimer’s and heart disease. It does not mean you will get either, and many carriers never do. If you are feeling the fear right now, start with does APOE4 shorten your life and the calm orientation in Start Here.
• Consumer raw data is not a clinical test. These genotyping chips are accurate for common, well-studied spots most of the time, but raw data is explicitly research-grade, not diagnostic, and errors do occur. For anything you would act on, confirm with a clinical-grade test ordered through a clinician.

The two SNPs that define APOE

Your APOE type (ε2, ε3, or ε4 on each chromosome) is set by two single-letter positions in the APOE gene, working together:

• rs429358
• rs7412

Think of them as two switches. Each one flips a single amino acid in the APOE protein (at positions 112 and 158), and it is the combination of the two switches, not either one alone, that determines whether a given chromosome carries ε2, ε3, or ε4. You inherit one copy of each from each parent, so each SNP shows up in your raw data as a pair of letters (a genotype).

You need both SNPs. Looking at only one will mislead you, because the same letter at rs429358 can mean different things depending on rs7412.

Step by step in 23andMe

1. Log in and open the search box (the magnifying glass, top right).
2. Search for Browse Raw Data and open it.
3. In the raw-data search field, type rs429358 and note the two-letter result under “Your Genotype.”
4. Clear it, type rs7412, and note that two-letter result too.
5. Look both up in the table below.

On AncestryDNA the path is Settings, then Download your DNA Raw Data; you then open the file and search it. Read the AncestryDNA catch below first, because many newer files are missing one of these two SNPs.

If a SNP does not show up at all: newer genotyping chips do not always include both positions, so a search may return nothing for rs429358 or rs7412. That is not an error you can fix by looking harder. It means your file simply was not genotyped at that spot, and you cannot determine your full APOE genotype from this data; you will need a clinical test. (Family Tree DNA files often include both SNPs if you have that data.)

What the combinations mean

These are the alleles as 23andMe reports them. At rs429358, a C is the marker for ε4. At rs7412, a T is the marker for ε2. Put the two together:

rs429358	rs7412	Your APOE genotype
T;T	T;T	ε2/ε2 (rare)
T;T	C;T	ε2/ε3
T;T	C;C	ε3/ε3 (most common)
C;T	C;C	ε3/ε4 (one copy of e4)
C;C	C;C	ε4/ε4 (two copies of e4)
C;T	C;T	usually ε2/ε4 (see note)

A few reading notes:

• The C;T / C;T case is the ambiguous one. It is standardly read as ε2/ε4, but an extremely rare variant called ε1 (which carries the ε4 marker at rs429358 and the ε2 marker at rs7412 on the same chromosome) can produce the identical raw-data pattern. This is the one combination where a clinical test is most worth it if the result matters to you.
• Order of the letters does not matter. “C;T” and “T;C” are the same thing.
• Other companies may flip the letters. Different services report different DNA strands, so a file from another provider can show the complementary letters (A/G instead of T/C). The table above is for 23andMe’s reporting; do not mix it with another provider’s raw letters without checking the strand.

The AncestryDNA catch

This one trips people up constantly: since 2017, AncestryDNA files generally do not include rs7412, one of the two SNPs you need. With only rs429358 you can often tell whether an ε4 is present, but you cannot reliably separate ε2 from ε3, so you cannot always pin down the full genotype. Files downloaded in 2015 to 2016 may contain APOE data that was later found to be unreliable. If your Ancestry file is missing rs7412, you will need 23andMe-style data or a clinical test to get the complete answer.

A note on privacy

Your genotype is sensitive information, and so is the fact that you went looking. Think about where this data lives: the testing company’s servers, any third-party analysis tool you upload to, and any screenshot you save. Read how we treat data on our privacy page, be deliberate about which tools you hand your raw file to, and remember you are under no obligation to share a result with anyone.

Okay, I found it. Now what?

Your next move depends on what you saw.

• If you carry one or two copies of ε4: breathe. For perspective, one copy (ε3/ε4) puts lifetime Alzheimer’s risk by age 85 in the rough range of 20 to 30%, and two copies (ε4/ε4) somewhere around 30 to 60%, against a 10 to 15% baseline. Those are real, but they also mean a large share of carriers never develop it. Then read what the Alzheimer’s risk numbers actually mean and focus on the levers you control. The cardiovascular and lifestyle factors are genuinely powerful, and they are where your energy is best spent.
• If you are ε3/ε3 or carry ε2: that is reassuring on the APOE axis, but it is not a free pass. Alzheimer’s and heart disease have many inputs, and the same healthy-habit levers still apply.
• For anything you would act on medically: confirm with a clinical-grade test and loop in a clinician or genetic counselor. This walkthrough is general education, not medical advice or a diagnosis.