What Is A Genealogy DNA Test?

What Is A Genealogy DNA Test?

DNA testing has recently become popular and mainstream due mainly to reduced costs and the continual Ancestry adverts you see on TV. But what is a genealogy DNA test and how can it help you with your family history research?What Is A Genealogy DNA Test?

Well, read on and I will explain it all to you.

When did DNA testing first start?

DNA testing became publicized in the late 1990s due to several cases that were brought to the public eye.

These cases used DNA to test whether there was any family connection between long-deceased people.

And so every day people became aware of this type of testing.

Who supplied the first tests?

The first company to offer genealogy DNA testing was FamilyTreeDNA. They offered DNA testing in May 2000.

The only testing though at that time that they could offer was to test male to male inheritance. This is referred to as Y-chromosome testing, (more on this later).

From then on the field of genealogy DNA testing has widened to include more tests.

And with the advancements in technology, it has become more affordable for the everyday public.

So, you too can get tested for under $100!

Please watch this!

The following short video from AncestryDNA can show you the potential of taking the test.

Credit:   AncestryDNA

Coupled with connecting with billions of genealogical records you can discover your family history.

Reasons to do a DNA test!

There are several reasons why you would want to do a DNA test.

These may vary from a paternity test to confirm a child’s father, forensic testing, or checking an unborn fetus for health problems.

And, also the main reason why you are thinking about a DNA test, and why you are here, is because you are interested in your genealogy!

Conducting a genealogy DNA test can help you to break down any brick walls that you may have encountered during your research.

If you have ever struggled to find a connection or want to know what step to next step then this type of testing can help you.

Please note: It must be pointed out that DNA testing is not used to determine genetic diseases or disorders.

This type of testing is only to provide genealogical information.

Check Out The Best DNA Testing Kits

What Is DNA?

To give its full title, DNA is short for deoxyribonucleic acid. It is described as a self-replicating material and can be found in all living organisms.

What Is DNA Markers?

DNA contains genetic information that can tell us what color eyes we have, or what color hair, or our skin color as well.

It’s inside all of us!

Nearly every cell within our human body has this same structure, this same DNA.

Nearly all of this information is contained within the cell nucleus. Some though is stored within mitochondria, (more on this later).

DNA therefore can give us genetic information about ourselves.

As we inherit characteristics from our parents it can also tell us about our family and therefore our ancestors.

What I find surprising about DNA is that 99.9% of this material is identical in all humans.

It is only 0.1 that differs and thus sets us apart from everybody else.

On Your Marks!

This variance in DNA sequences is called genetic markers. These markers are then used by scientists to perform tests and to see the difference between people.

By testing these markers we can also see how closely two people are related.

(As a side note identical twins are, as the name suggests, identical and as such, they have identical markers).

The trouble though with this testing is to know where to look. There are billions of codes that we need to sift through to find these markers.

I won’t go any further with the details about DNA as it can get pretty complicated, and that is not the aim of this post.

So, next, I will discuss the different types of DNA testing that are available to you and which companies can provide this form of genealogy research.

What Types Of DNA Testing Are There?

In the beginning, there were only two forms of DNA testing that were available. With the advancement of technology and tools, genealogy testing can now be broken down into four types.

Each of these tests can help with a different aspect of your genealogical research.

The 4 types of DNA testing:

Each of these tests looks at spots or markers in our DNA that change slowly over time. These markers are inherited from our parents.

Closely related people will have the same DNA signature. Unrelated people will have a different signature.

Commercial DNA testing companies such as 23andMe, AncestryDNA, and FamilyTreeDNA provide a swab or spit kit.

There are also centers where you can visit where you can do this test.

You can expect results for these to take between 6 to 8 weeks.

How Many Chromosomes Do We Have?

Before I explain the different types of genealogy DNA testing I will first briefly describe what DNA and chromosomes are.

We each carry 23 pairs of chromosomes, where a chromosome is a thread-like structure that carries genetic information in the form of genes.

How Many Chromosomes Do We Have

So, our DNA is a specific set of instructions that make up each one of us.

Within each of these pairs we carry one chromosome from our father, and the other from our mother.

The first 22 pairs are called autosomes, and this is information that has been passed down from generation to generation.

The 23rd pair is known as the sex chromosome, and this is what makes us male or female.

Y-chromosome (yDNA)

This DNA test looks at the Y chromosome which is passed down the paternal line from father to son. This test is only suitable for males.

Father and Son

As a result of this female genealogists will have to ask their father, brother, uncle, or male cousins to do the test.

Results are compared for this chromosome and checked against males to see if there is a match.

They are also checked to see if they are related in a genealogical timeframe.

From this test, the haplogroup is also obtained. The haplogroup defines deep ancestry and can be broken down into ethnicity such as European, Asian, and African.

There are though other haplogroup groups and interest projects.

Mitochondrial DNA (mtDNA)

The mitochondrial DNA is passed on from the mother to her sons and daughters. However, although males carry this information only females will pass it on.

Mitochondrial DNA

Through this test, you can also obtain the haplogroup to check for deep ancestry.

Mutations are compared to see if anyone shares a common ancestor in a genealogical timeframe.

As this tests the maternal line your ancestors’ surnames will change with every generation.

With this test it is far more difficult to make connections, so you may not be able to make sense of the results and benefit from them fully.

Autosomal DNA (atDNA)

This tests the 22 pairs of autosomes that come from both parents. The three big companies 23andMe, AncestryDNA, and FamilyTreeDNA all offer this testing.

Special Family Days

They can test over 700,000 markers and provide you with a list of cousins from all of your branches. Autosomal DNA testing can also determine common ancestors.

Information is filtered as it is passed down to you and so some markers may not be present in your DNA.

You may even receive varying results from different companies.

This is basically because they each have their distinct way to class your DNA.

The autosomal test will give you results for only 4 to 5 generations back.

So, before you decide to take this type of DNA test it is best to first consider how useful the results will be for you.

X-chromosome (xDNA)

This test is different from the mitochondrial DNA test that looks at the maternal line. Men have an X and Y chromosome, whereas women have two X chromosomes.

Incidentally, the Y chromosome is passed on from the father.


Men will inherit one X chromosome which is from their mother. Women however will receive two X chromosomes, coming from both parents.

The inheritance path for X chromosomes is therefore different for both men and women as not all ancestors will contribute to this X chromosome.

As this is a new type of testing the three main genealogy DNA companies do not offer this.

What Do The Genealogy DNA Companies Offer?

FamilyTreeDNA is the only company to offer full genealogy DNA testing covering the first three types.

23andMe does offer atDNA testing and also very low predictions concerning yDNA and mtDNA.

The third most popular company AncestryDNA only offers atDNA testing.

There is at present only one company that offers the fourth type of testing and they are deCODE genetics.

These companies do operate in the US but they can ship your tests and results to any country. Shipping will take longer if you live outside the US.

There are plans by these companies to operate in the UK and Australia. This will save you both money and time waiting for tests and results.

Please note: I will be covering the three main genealogy DNA companies in future posts.

Your DNA Data and Privacy!

One concern that you may have before you decide to take this next step is the privacy of your DNA data. After all, it is essentially your information and who knows what can be done with it in the wrong hands.

All of the DNA testing companies that I have reviewed on this site have stated and assured that your DNA data is not shared with any third party.

I would like to share with you an article by Victoria Mcintosh entitled DNA testing kits: What are the privacy risks.

My Final Thoughts!

Genealogy DNA testing has provided many family historians with the clues they need to get past brick walls that they may have encountered during their research.

It is also enabled them to connect with distant cousins who they did not even know existed before they even carried out this type of testing.

However, before you do conduct this type of testing I would suggest that you have researched your family tree for a while.

If you do get stuck along the way then why not use DNA testing to pass that hurdle.

Finding distant relatives can also be a bonus to you as they can share with you information that they know about their side of the family.

Resources to help your DNA testing!

There are a few DNA genealogy books that I recommend that will help you with this type of research.

These books will cover what types of testing are available to you in more detail. I have only scratched the surface here as I wanted to be brief and point in you the right direction for more guidance.

These books can also help you to fathom the results that you will get back.

The results returned to you may baffle you so it is well worth having a guidebook that will help you to interpret these results and ultimately help you go further with your research.

Did you know that you can improve your genes through meditation?

Well, to find out why not visit Medit Sounds for more information.

Medit Sounds

Thank You and Please Leave A Comment

I hope you enjoyed this guide to what is a genealogy DNA test. If you have any questions or comments then please leave a comment below.

Please share with family and friends if you think this post will help others by using the social media buttons below.

Article Name
What Is A Genealogy DNA Test?
What is a genealogy DNA test and how can it help with your family history research? Discover the different tests that are available and how they can help you.
Publisher Name
The Genealogy Guide
Publisher Logo

22 thoughts on “What Is A Genealogy DNA Test?”

  1. I agree with the previous comments, we know very little about DNA tests. Your blog contains amazingly important and useful content. Thanks so much for your work! Good luck!

    1. Hi Joan,

      The prices for the three major companies in the US range from $79 to $99, but you will have to add a further $10 or so for shipping. The major companies are FamilyTreeDNA, AncestryDNA and 23andMe. Each of these do offer different kind of testing as I have mentioned in this article. I will be reviewing each of these in turn in the near future. But I do recommend FamilyTreeDNA as it does offer full testing.


  2. This was a very interesting article. I had no idea that DNA testing could help with genealogy research, let alone that there was more then one kind. You explained it very well. I learned a lot and I will be looking forward to more of your posts on this.

    1. I am glad that you enjoyed and learned from this article. I will be posting in the near future reviews of the big companies offering DNA testing. Stay tuned.

  3. Really interesting reading. I never knew that men only inherit one X chromosome from their mothers, while women get two from both parents. I also never knew that there were so many different types of DNA Tests that can be done.

    I just wondered how you would get DNA from all your ancestors. This is a bit mind boggling to me.

    1. These tests can tell you from where your ancestors came from. So they can give you clues to your past. They are well worth checking out as they can break down brick walls in your research as well as make connections toons with living relatives

  4. The way you elaborated here is exactly the kind of thing I would be interested in.
    What do I mean? Well, not enough information about this topic is written down plainly for all to understand, and the way you broke it down makes it very simple even for someone like me, who has no idea how genetics work.
    Keep up the good work!

  5. I love science and your site contains just that!! I did not know there were so many classifications for DNA, let alone ways to actually research your Genealogy. I’ve had the opportunity to do some research into my own genealogy and all I had to say was, “WOW” this stuff goes back years. This is great information and it’s very helpful.

    1. Lol, this stuff goes back years. True indeed. It is a fascinating subject and DNA eating is a new and interesting field of research. Thank you for finding it helpful.

  6. This is the most fascinating article I’ve read all day. I see the Ancestry. com commercials and they are very intriguing. I think it’s pretty cool to learn about your ancestry and to see where your lineage starts. I think this was a great article because I never really thought about how it’s possible to research your family line. You demystified the whole thing for me. I knew it involved DNA testing but I did not know that there were different companies that test for different sets of chromosomes This was all very informative and I think more people should research the type of DNA testing they want because each can pull different results. Great read!

    1. This is just one way to research your family history and like you said it is fascinating. I am glad that I demystified it for you as it can be quite confusing what with all the chromosomes and the tests that there are. You may like to check out my What DNA Genealogy Book Shall I Buy? article for more information

  7. My god. As you would expect not much people know an awful lot about this kind of stuff, me being one. Great to read and find out the different types of DNA testing that gets done as I only thought there was 1. Great post and really interesting.

    1. As genealogy is such a wide subject it can be broken down into many areas. That said it is best to research these areas and know what you are getting it, so that you can get the most from them. So this post highlighted what it is all about.mi am glad that you liked it.

  8. Hal's Review of Body Weighing Scale Ebsite

    Great reading, Owain!

    I wonder how far back in one’s history the DNA genealogy goes, and how accurately it can pinpoint a relative. I recently came across an article that led me to believe that there’s a chance, albeit very small, that I might be related to a Jewish pirate who served the famous pirate Henry Morgan. I’ve always gravitated toward Reggae and island music (I’m a musician myself. This fellow and Henry Morgan, too…spent their golden years in Jamaica. Both my parents are gone, so I don’t have anyone oder in my family to ask about it. So DNA testing might be the only way to go at this point. I’ll definitely have to consider it.

    Thanks for such an informative and interesting site!

    1. Apparently the Y-Chromosome can be used to trace back 135,000, and the mitochondrial back about 200,000. I doubt though that these companies would offer you this service though, lol.

      That is a very interesting connection, if it is true. I have heard of Henry Morgan and know that he sailed around Jamaica. Whether you would be able to prove this I am not so sure, but it’s still worth trying. Who knows you might something else quite interesting with this kind of research

  9. Interesting article Owain, I never really took the time to read about DNAs even though I am interested in every latest science and tech. You offered in-depth information on the topic and also provided services we can use to find out more about our genealogy. Highly appreciated. Regards.

    1. I quite enjoyed writing this article so thank you for appreciating it. DNA testing is another way of researching your family history and certainly needs to be considered when you are ready to do so.

Leave a Comment

Your email address will not be published. Required fields are marked *