Last updated: January 13, 2025
AncestryDNA Sideview™ now estimates your parents’ ancestral regions–without them even taking a test! They can do this because of the massive size of their database and the use of phasing. What is phasing? Here’s a quick, easy explanation of this exciting technology.
In April 2022, Ancestry released a new technology called Sideview™ that empowers discoveries about each of your parents’ sides of the family–even if your parents themselves have not taken DNA tests! This is the first time any company has been able to do this, just by looking at your DNA and your matches. The tool estimates your parents’ ethnicities–and more is coming.
Here’s a video introduction and article to help get you up to speed on this exciting feature.
As exciting as SideView™ is, it’s only one manifestation of the even BIGGER SCIENCE that is fueling this feature: phasing.
What is phasing?
SideView™ is a technology that builds on and improves the technology of phasing. Remember, you have two copies of each chromosome. Phasing is the process of reconstructing those two chromosomes for each parent at each chromosome. In this article we explain that phasing is like taking two similar sentences and trying to figure out the order of the words in each sentence.
Keep reading. You’ll see how phasing works–colorfully–in the explanation below.
Ancestry’s SideView™ Technology
Actually, Ancestry has been phasing your data for years. However, previous phasing technology relied on DNA databases that could report which sections of DNA most people had most of the time, but it wasn’t personal to you. Or, to build on our sentence analogy, previous phasing technology has a list of most-often-seen phrases that they then use to reconstruct your most likely sentence structure for each parent.
But this new SideView™ technology is different. Instead of using a database of best-guesses, they are reconstructing your two parents’ chromosomes based on the DNA you share with your DNA Matches. This works because you are only sharing DNA with any given match on just one of your chromosome pairs, not both. (The two exceptions to that rule are in cases of endogamy, or for your sibling or their descendants). This is only possible because of Ancestry’s large database of over 20 million people tested.
Here’s how it works:
Let’s say these are the two chromosome 9’s you received from your parents (one from mom, one from dad):
Ancestry tests your DNA, and it comes out in a mixed up jumbled up mess, like this:
With the SideView technology, Ancestry identifies individuals in the database who share DNA with you and with each other, and they become pieces of your chromosome puzzle. The locations where your puzzle pieces connect are actually overlapping DNA segments, which ensure they are assembling your chromosome correctly:
The result is a reconstruction of your two copies of chromosome 9. One you received from your mom, and one from your dad.
Ancestry is just starting to tap into the power of this technology with their first feature. You can now see which ethnicity results came from your mom, and which you received from your dad.
So does it work? Ancestry’s science team reports that for 90% of its customers, it will work greater than 95% of the time. That’s pretty amazing. And those other 10%? Well, you know who you are (maybe). You are those who have significant endogamy (the practice of marrying within the same culture or location for several generations) in your family tree.
Exploring your ethnicity inheritance by parent
Ancestry allows you to view your ancestral regions and journeys inherited by parent. (This feature was previously called Ethnicity Inheritance.) To access this feature, you’ll need to take an AncestryDNA test if you haven’t already, and an AncestryDNA Plus or full Ancestry subscription.
Then log in to your results. Go to DNA > Origins > select the By Parent tab. You can view ancestral regions, ancestral journeys, and chromosome painter by parent. We’re going to look at Ancestral regions by parent, so click on that option.

Options in AncestryDNA to view DNA Origins by parent, from left to right: ancestral regions by parent, ancestral journeys by parent, and chromosome painter
On this page you will see the same results with two views. First, you will see a side-by-side view of your ethnicity results with the new parent split on the left, and the full you on the right. I’ve assigned a side as my Paternal side and the other side as my Maternal side, but when you first view this feature, you’ll see them labeled Parent 1 and Parent 2. You can update this at any time by clicking Edit parent labels. Remember that Parent 1 could be your mom or your dad.
Underneath this view you will find a detailed view. This is just the same information broken down by percentage.
What next?
What should you do with this information? Start by taking a look at your breakdowns to see if you can identify which of your parents is Parent 1 and which is Parent 2 so that you can assign each parent as “Maternal” or “Paternal.”
If possible, identify which specific ancestor on your mom’s side or dad’s side may have contributed that amount of shared DNA. Then look for any ethnicities that are not already represented in your family tree, and note which parent’s line contains that ancestor(s) contributing those percentages.
More will ALWAYS be coming in DNA discoveries. That’s why we created the AncestryDNA Tour with Your DNA Guide. This on-demand experience helps you understand EVERYTHING you can get from your DNA test results–including SideView at Ancestry! Your Tour includes a series of short video tutorials (about 90 minutes in total) and companion activities that help you apply what you learn to your own results. You can revisit your Tour anytime you like, and your companion workbook and quick reference guide become a useful reference for you as you continue to explore your AncestryDNA results in the future.
Update (September 2022): AncestryDNA can now assign matches to each of your parents’ sides of the family. Read more here.