Getting the Most Out of Your DNA Results

DNA testing is revolutionizing how we explore our heritage, but not all features are equally useful for specific research purposes. As a DNA Subject Matter Expert who’s been working in MyHeritage’s Customer Support for the past 4 years, I find that the most valuable tool for researching your origins is actually not the one most users get excited about.

But before I dive into the various aspects of DNA testing and how to make the most of it, let’s begin with how DNA matching works.

Autosomal DNA

Our test at MyHeritage analyzes segments of 22 of your 23 chromosome pairs: your autosomal DNA (atDNA). The test doesn’t examine the 23rd chromosome — also known as the sex chromosome — where your X and Y DNA are examined. We also do not currently offer a mitochondrial DNA test.

Each chromosome consists of two long DNA strands, structured like a twisted ladder (a double helix). These strands contain a sequence of four chemical bases: adenine (A), thymine (T), guanine (G), and cytosine (C), attached to a sugar called deoxyribose. We inherit one strand from each parent, forming complete chromosome pairs. Take a look at the illustration below:

The four chemical bases of DNA

We can define a SNP as a variation at a specific position on the genome (as shown in the image below): one little point with information in it. There are millions of SNPs in the human genome, but most of our DNA is the same and performs the same functions. Therefore, for genealogical purposes, atDNA tests typically cover around 700,000 SNPs:

A DNA base pair

What we call “DNA segments” are continuous stretches of SNPs on a chromosome that help identify shared ancestry. Below is an example of a DNA segment found on a chromosome:

A DNA segment with 3 SNPs highlighted

Keeping the above explanation in mind, when it comes to a standard autosomal DNA test from one of the major consumer DNA testing companies — ours included — the main two features that you will be exposed to are usually an ethnicity estimate, and a platform for exploring DNA matches (other people in the database whose DNA matches yours). Both are fascinating features that can reveal a lot about your genetic origins.

The Ethnicity Estimate

The Ethnicity Estimate offers a simplified evaluation of your ethnic origins. Based on autosomal DNA (atDNA), this part of your results analyses roughly 700,000 SNPs (single nucleotide polymorphisms) across your genome. It compares your genetic markers to reference populations in the company’s database to estimate where your ancestors likely lived.

Here’s the thing: it’s called an estimate for a reason. The results you receive are constrained by the populations included in the company’s reference panel, which can vary widely between providers. At MyHeritage, we are happy to be able to compare your DNA to 79 reference populations as of the latest version of our estimate. 

The ethnicity breakdown also has limitations based on geography and historical context. Populations have migrated, intermarried, and evolved over time and as a consequence, the boundaries of genetic “ethnicities” don’t correspond perfectly to modern borders. Even within regions, significant overlap often exists between neighboring populations. A little Scandinavian DNA showing up in your results doesn’t necessarily mean your ancestors were Viking raiders — it could just as easily mean that trade or migration brought those genes into your pool. Often, in cases like this, the events took place too far back in history to verify. Many people who test their DNA find that their personal narratives — those they base their identity on — are challenged. However, it’s important to keep in mind that as interesting and informative as this feature is, it’s still just an estimate. There is so much more to your genetic story than these results.

In light of this, I would advise DNA testers to view this estimate as more of a brush stroke regarding their genetic heritage, instead of a detailed portrait. The estimate should also be a catalyst for further exploration. It invites you to ask yourself: 

• “Does this align with what I already know?” 
• “Why or why not?” 
• And most importantly, “Does it provide clues for further investigation?”

In many cases, the estimate does provide clues that should prompt further research. Though it may not be precise, it is still a valuable tool.

Matching segments

As mentioned, a DNA segment is a sequence of SNPs on a chromosome. In your autosomal test, we take your DNA data and compare it to the other DNA kits in our database to try and find sequences that look similar to yours among the DNA of others in our database.

Segments that you have in common with your DNA matches can vary in length depending on how far back your common ancestor is. We call these segments “Identical By Descent” or IBD for short. These sequences are measured in a unit which we refer to as centimorgans (cM).

In my experience, the real goldmine you receive when you take a DNA test is your list of DNA matches.

Your DNA Matches on MyHeritage

Here’s why it’s worth delving further into your matches:

Direct Data: Unlike Ethnicity Estimates, which are based on reference models, DNA Matches rely on measurable data — segments of shared DNA — rather than an estimate.

It’s Actionable: Depending on the company that you test your DNA with, you can use various tools to triangulate relationships, explore family clusters, and pinpoint common ancestors with your matches within a range of 6 generations back.

Collaboration: MyHeritage allows you to contact your matches, which can lead to information-sharing and new discoveries. There is also an incredible feature called the Theory of Family Relativity™ that ties in with the family tree platform. 

It is very important to understand that if you wish to progress further back in your family research, and to discover more about your origins, your DNA test goes hand in hand with your genealogical research — that is, building your family tree and exploring evidence about your ancestors recorded in historical documents.

Come explore with me at RootsTech!

At the upcoming RootsTech Conference in Utah, I’ll explore how to analyze DNA matches effectively and avoid common research pitfalls. I’ll also address frequently asked questions and share practical strategies to help you overcome challenges. My goal is to help you maximize your DNA matches for more accurate genealogy research.

Drop by the MyHeritage booth on Thursday, March 6, at 11:00 A.M. or Saturday, March 8, at 2 P.M. to join me! I look forward to seeing you there.

Alex Findlay

Alex Findlay was born in South Africa and graduated with a degree in Social Science from the University of KwaZulu-Natal in 2006. He has also recently completed a Master’s in History at the University of Birmingham. In 2009, he and his wife immigrated to Israel, and since joining MyHeritage in 2020, he has transitioned from a core support role to that of a Subject Matter Expert, specializing in the company’s DNA platform.