How does AncestryDNA® work? An inside look at the process.

You may know that AncestryDNA can tell you about your family history using nothing more than a small saliva sample. But exactly how do we do it? How does DNA testing work and what goes on behind the scenes as we transform your DNA into your ethnicity estimate, ancestor migrations, and DNA matches?

Getting started with AncestryDNA.

You can easily purchase AncestryDNA online. We’ll send you a DNA kit that includes a sample tube, a pre-paid envelope to mail your sample to us, a unique activation code, and instructions for how it all works.

Once you receive your kit, you will also need an online Ancestry account if you don’t already have one. Each AncestryDNA test must be linked to a unique account—one for each test. The only exception is tests for children and minors, which can be added onto the account of a parent or legal guardian.

Once the activation code for your DNA test is entered into your Ancestry account, the two are linked and your account will be where you manage and view your DNA test results and DNA matches.

Collecting and submitting your DNA sample.

Your sample tube is enclosed in your DNA kit. Although the science behind it is impressive, using it is fairly straightforward.

  1. Fill the tube with saliva, up to the line indicated. Don’t worry, it’s a small tube and isn’t hard to fill.

    • Once you have filled the tube, screw the provided cap on securely until a blue fluid is released from the cap into the tube. This is an additive designed to preserve your DNA and make the testing process easier.

  2. Then shake the tube for five seconds to distribute the additive and seal it in the provided envelope.

  3. Mail the envelope back to us. Postage is already included to send your sample via U.S. mail, so please make sure not to send it with a different carrier.

Analyzing your DNA sample.

After we receive it, our lab uses a state-of-the-art process to isolate your autosomal DNA from your saliva sample. This kind of DNA test provides a more complete genetic picture of you compared to other types of DNA tests. For instance, the mtDNA used in some tests only shows your matrilineal heritage, or your female ancestors. Y-DNA tests only show patrilineal, or male ancestors and can only be taken by men or male relatives.

An autosomal DNA test, the kind that we use at AncestryDNA, lets us see both sides of your family and can be taken by anyone. It also lets us find information about you across much more of your DNA, sampling hundreds of thousands of positions, or markers, for a more detailed picture of who you are and where you’re from.

Get a behind-the-scenes look at how AncestryDNA works.

DNA markers and what they can tell us.

Those markers that we search for weren’t chosen at random. They are places where peoples’ DNA differs slightly, called “single nucleotide polymorphisms,” or SNPs. You inherited your DNA from your parents, including those SNPs, so we can use their presence—or absence—to trace your ancestors back in time.

Calculating your ethnicity estimate

AncestryDNA has spent years assembling a huge database of DNA samples, collected from people with deep ancestral roots in certain geographic regions. This “reference panel” of samples helps us identify different regions around the world, since people from certain regions or groups often share similarities with each other in the patterns of their SNPs. If we also find those patterns in your DNA, it can reveal a connection. That allows us to build your ethnicity estimate.

Drawing even more information from your DNA

We can also compare markers in your DNA to other users in our database to find family connections. By combining this data with historical records and family data, we can identify more than 350 different regions, which can tell you about the communities and migration patterns of your ancestors in even greater detail.

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