Why Are Your DNA Results Different From Your Parents?

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Do you wonder why your DNA results are different from your parents? In this post, learn all about how and why our results are different from our mother and father’s results.

You will discover answers to the following questions:

• Can you have a larger ethnicity percentage than your parents?
• How much genetic information comes from each parent
• Can DNA ethnicity skip a generation
• Do you get more ethnicity from mom or dad?
• How much ethnicity do you get from each parent?
• Can you have DNA that your parents don’t?
• And much more!

When I did my first DNA test back in 2016, I was amazed at the information in my results. Then, I realized that if my parents also took tests, I could learn even more.

Of course, one of the first things that people do when they see their results compared to those of their parents is check to see how they are different. This process can occasionally be confusing.

For example, you might have noticed that your parents have regions in their ethnicity estimates that don’t match yours at all. Or, you might have more DNA matching a region than both of your parents combined.

You are not alone in wondering about these details of your results.

Why DNA results are so different from mom or dad

Our DNA results are different from our parents because we do not inherit all of our mother and father’s DNA. We inherit only a portion of our parents’ DNA, which means that our DNA will not exactly match our mother or our father.

The DNA that is passed down from our parents to us is selected at random during a process called “recombination“. Every human has two copies of 22 numbered chromosomes.

The recombination process selects some DNA from each copy of our parent’s numbered chromosomes in order to make a brand-new, completely unique chromosome for us. We inherit one copy of each chromosome from each of our parents.

On each numbered chromosome is the autosomal DNA that is tested in order to determine where our ancestors may have lived, as well as our DNA matches. Since our autosomal DNA is not exactly the same as that of our parents, our results reflect the difference.

How much genetic information comes from each parent

Each person inherits almost exactly 50% of their DNA from their mother and father. The genetic information passed down from our parents can include, depending on our biological gender, autosomal DNA, Y-DNA, mitochondrial DNA and X-DNA.

As I mentioned above, every male or female human has 22 numbered chromosomes. Half of the DNA on each numbered chromosome is passed down from each parent in a brand-new copy for their child.

Do you get more DNA from mom or dad?

The result of this pattern of DNA inheritance is that every child will inherit 50% of their autosomal DNA from both of their parents. Even if a child looks more like one parent than another, we can be sure that they share the same percentage of autosomal DNA with both of their parents.

For the sake of accuracy, we must note that there are also types of DNA that children inherit from their parents. For example, both males and females inherit X-DNA and mitochondrial DNA (mtDNA) from their mothers.

Males also always pass down other types of DNA to their children, such as Y-DNA to their male offspring. In addition, males pass down a full X-chromosome to their female children.

From a technical standpoint, we might inherit more overall DNA from our mothers, since her mitochondrial DNA is contained within almost every cell in our body. However, even taking all of these different types of DNA into consideration, everyone shares just about half of their DNA with both parents.

Since most people who are reading this article are curious about why their DNA results are not the same as those of their parents, we will focus primarily on autosomal DNA testing results. This is the type of DNA tested by Ancestry, MyHeritage, and the focus of ancestry tests offered by companies such as 23andMe and Family Tree DNA.

Do you get more ethnicity from mom or dad?

The type of DNA that is examined for ethnicity testing is the autosomal DNA that is located on our numbered chromosomes, which comes in equal percentages from both of our parents. This means that we inherited the same amount of DNA that is analyzed for ethnicity from mom and dad, and that we did not inherit more ethnicity from one or the other.

Before we continue, it is important to note that describing ethnicity as being “inherited” or “passed down” is a misnomer, of sorts. We cannot truly inherit ethnicity, since to have an ethnicity is to belong to a social, cultural, linguistic, or even a national group that has a common, shared identity.

However, the advanced technology of DNA testing is able to identify where in the world our ancestors may have lived, and in some cases, the ethnic groups to which they likely belonged. Thus, the “ethnicity estimate“.

So, while we do indirectly “inherit” ethnicity in a sense, the data used to determine our ethnicity estimate is really coming from the autosomal DNA that is tested.

Can you have a larger ethnicity percentage than your parents?

You can have a larger percentage of an ethnicity region on your DNA results than one of your parents. The main reason that this occurs is when you inherited some DNA matching the region from both parents.

For example, if 20% of your father’s DNA matching the Germanic Europe region and 20% of your mother’s DNA matches the same region, it is possible for you to show as much as 40% Germanic Europe DNA on your results.

This might seem strange, since towards the beginning of this article you learned that you inherit only 50% of each parent’s DNA. However, since the 50% of your mother and father’s DNA that is passed down to you is randomly selected, it is possible for you to inherit 100% of their ethnicity matching a particular region.

If both of your parents have ancestry from the same region, your results could show a higher percentage matching that region than theirs does.

Most people do not have DNA results for both of their parents. If one parent takes a test, we might be surprised to have more DNA matching some of their regions than they do.

In these circumstances, it is important to take into account the possibility that the other parent (the one who did not or could not take a DNA test) may have had ancestry from the same region. This would easily explain why we would have more DNA from a region than one of our parents.

How can I have more DNA ethnicity than my parents

What if you and both of your parents took a DNA test and the total percentage of DNA matching an ethnicity region equals more than their percentages combined? More confusing still, what if you have DNA from a region that does not match either of your parents?

While unusual, these situations do occasionally occur.

If you and your parents tested at different testing companies, it is impossible to make 1:1 comparisons between ethnicity estimates. Differences in technology, reference panels, and sample populations between companies, as well as even the name of the ethnicity region and corresponding area can cause a lot of confusion.

If you and your mother and father all took a DNA test at the same major testing company, such as Ancestry DNA and 23andMe and you share the expected number of centimorgans with each of your parents, you could still see discrepancies between your results and theirs.

Occasionally, we do see a child with more ethnicity from a region than both parents combined, or even a region that neither parent saw on their results. This error in our results is only due to our DNA seemingly to appear more like DNA from an adjacent region.

For example, if my mother has 10% of her DNA matching Norway, and my father has 10% matching Norway, and I show 8% matching Sweden, I could just assume that the algorithm is confusing Norway for Sweden. I would not truly view this as an error, since people from both of these countries have a lot overlap in their genetic origins, and it is understandable that a developing algorithm could confuse them.

It is important to remember that the science for exploring ethnicity through DNA is still developing. In addition, the DNA of humans is almost identical, which means that DNA testing examines minute differences between us that can occasionally be misinterpreted.

Can DNA ethnicity skip a generation

DNA ethnicity cannot skip a generation. In other words, if our grandparents had DNA that did not show up for our parents, it cannot show up in our results.

If we have DNA in our results, such as our ethnicity estimate, that does not match our parents, it must be because of the scenario that I mentioned previously in the article about DNA from adjacent or nearby regions. If it just happens to match a region that we assume that our grandparent may have had, it is a simple coincidence, since DNA does not skip generations.

Is DNA passed down from generation to generation?

Yes, DNA is always passed down from generation to generation. However, since we only inherit 50% of our genes from each parent, there is DNA that is not passed down to the next generation.

This is the reason why we do not share DNA with all of our ancestors or with all of our relatives.

Conclusion

I hope that this post has helped you understand more about why your DNA results are different from those of your parents. The way that DNA is inherited is fascinating, and at times even confusing.

However, the more you learn on the topic, the easier it will be to use your results to understand where your ancestors lived and build your family tree using your results.

If you have any questions about something that you read in this post, or if you would like to share a surprising way that your results are different from your parent’s results, I would love to hear from you in the discussion below.

Thanks for stopping by today!

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