Is It Possible to Not Have Any DNA Matches From an Ancestor?

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If you have spent some time analyzing your DNA match list, you might wonder if it is possible to have no DNA matches from an ancestor who you know is in your family tree. In this post, learn whether this is possible and how it could happen.

I’ve thought a lot about the question of whether it is possible to not have any DNA matches from an ancestor. There are several ancestors in my family tree who don’t seem to be represented by relatives on my DNA match list.

In other words, I have a lot of DNA matches who descend from many of my known ancestors. However, when I look for DNA matches descended from some of my ancestors, I can’t find anyone.

If you’ve noticed this, too, it might puzzle you.

Does it mean that you are not really descended from that ancestor, or that you didn’t inherit any of their DNA?

While it is true that we can have mistakes in our family trees, there is usually another explanation for this phenomenon. In this post, find the reasons why you don’t see DNA matches descended from any specific ancestors.

Your cousins haven’t take a DNA test yet

The most common reason that you can’t find any DNA matches descended from an ancestor is because your cousins on that line of your tree haven’t yet taken a DNA test. This is the most likely explanation when your ancestor is relatively recent, or when your ancestor was born in a country where DNA testing is not popular.

The reason that we are less likely to find DNA matches descended from a recent ancestor is because we have fewer of these types of relatives. My paternal grandfather, for example, only has two children, five grandchildren and seven great-grandchildren – a total of fourteen descendants.

If we go back further in our family trees, we are much more likely to find some of our ancestors’ descendants among our DNA matches. For example, some of my great-great grandparents have dozens of descendants, making it more probably that a few of them have taken a DNA test.

Along this same line of thinking, if our ancestor was born in a country where DNA testing is not popular, it’s much less likely that their other descendants have tested their DNA. They might do so eventually, however, so make sure to occasionally check your DNA matches for updates.

One of my great-great grandfathers was born in present-day Slovakia to a large family, but I haven’t been able to identify any DNA matches who are also descended from his father (my great-great-great grandfather).

If his eight children each had three children, and every descendant in the subsequent generations had an average of three children, this ancestor could have as many as 648 descendants in my generation. But since my great-great grandfather was the only one of his siblings to come live in the US, most of my Slovak cousins likely live in Slovakia, a country where consumer DNA testing is not as popular as it is in the US.

Your cousins might have tested with a different company

Your cousins may have tested, but they might have done so with a different DNA testing company. This is one reason that I recommend testing with more than one company and/or uploading your DNA information to additional companies’ databases when possible.

If you test with other companies, you might find that the cousins descended from your ancestor do show up on those DNA match lists.

I did my first DNA test with Ancestry and I didn’t see any DNA matches who were descended from my mother’s paternal grandparents. Eventually, I decided to test with another company and found that several of my cousins on that side of the family had tested with 23andMe.

Your ancestor doesn’t have a lot of living descendants

Some of our ancestors don’t have a lot of living descendants. Whether any given ancestor has many descendants depends on many factors, such as how many children they had, as well as environmental factors.

One of my great-great grandfathers, born in Holland, had six children, four daughters and two sons. One daughter died as she entered adulthood, and the other three daughters married but had no children. One son had two kids, but the only one who survived to adulthood never married.

The third son, my great-grandfather, only had three children. While his all of his three children did go on to start families of their own, his is the only line of my Dutch great-great grandfather that produced descendants.

There simply aren’t very many people on this line of my tree to take a DNA test and show up on my list of genetic relatives.

The DNA matches might be there, but you haven’t yet figured out how you are related

It’s very possible that you actually do have DNA matches descended from the ancestor you are researching, but you don’t know it. This is a likely explanation when you have many DNA matches without a family tree linked to their profile, or when they only have very small trees that only display a couple of generations of ancestors.

If you think that this explanation might apply to you, there is no need to worry. There are many things that you can do to figure out how you are related to your DNA matches, including building a quick and dirty tree for them (which is easy if they already have a small tree!).

You and your cousins didn’t inherit the same DNA from your shared ancestor

Your cousins descended from the ancestor that you are researching may not have inherited the same DNA from your shared ancestor. As the number of generations back to your shared ancestor grows, the less likely it is that you and other people descended from that ancestor inherited identical DNA segments.

In this scenario, it doesn’t mean that you didn’t get any DNA from your ancestor. It simply means that you and your cousins inherited different DNA from that shared ancestor, which would explain why they don’t show up as DNA matches for you.

This explanation is most likely for descendants of our more distant ancestors. For example, we only share DNA with about 50% of our 4th cousins.

This means that even though we did inherit DNA from our 3rd great-grandparents (the ancestor we share in common with our 4th cousins), we won’t have identical DNA segments shared with 50% of our many fourth cousins on that line of our tree.

If very few of your 4th cousins have taken a DNA test on the line of the ancestor you are researching, then it is possible that the only cousins who tested are those with whom you share no DNA. Thus, they would not show up on your list.

The good news is that we do have a very large number of fourth, fifth, and sixth cousins (and so on!), and so there is a high probability that new DNA matches descended from those more distant ancestors will show up in the future.

You might not have inherited any DNA from your ancestor

Finally, there is a possibility that you did not inherit any DNA from the ancestor that you are researching. This is only possible for very distant ancestors, as we do share DNA with all of our recent ancestors.

As we go further back in our tree, it becomes less likely that we inherited DNA from any specific ancestor. For example, there is a 37% chance of having inherited no DNA from a 7th great-grandparent.

If you go back even further, such as to the 14th great-grandparent distance, there is only a 1.5% chance that we did inherit DNA from any given ancestor on that generation. It is impossible to have inherited DNA from all of our ancestors – our genome is not big enough to hold DNA from all of them.

This is why, even though I am descended from John and Priscilla Alden, I would probably not match them on a DNA test. They are only two of my more than 8,000 11th great-grandparents, and I only inherited DNA from some of them.

It’s also why even though I, along with anyone else who had ancestors in Europe in the past several hundred years, am probably descended from Charlemagne, I would be unlikely to show a genetic relationship to him.

(And even if I did have a genetic relationship to him, it would be impossible to prove that the DNA we both share was inherited from him and not an ancestor that we both share. So complicated!)

Even if you didn’t inherit DNA from an ancestor, it doesn’t diminish your relationship to them. You are still their descendant, and you are still related to all of their other descendants.

Conclusion

I hope that this article about why you might not have DNA matches descended from some of your ancestors has helped you understand the topic. If you have any questions about something that you have read here, or if you have a specific question about DNA matches descended from one of your ancestors, please join us in the discussion below.

Thanks for reading today!

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