Using Autosomal DNA to Identify Biological Relatives

For those of you at the start of their journey to find their biological family, we at The Adoption Specialist suggest the first step you take be to order a DNA test.

How Can a DNA Test Help With my Search?

Often people looking for their birth families are entering into their search with little to no information – no birth certificate, adoption records, names, places or dates. 


That does not however mean that they have already hit a brick wall!

By undertaking a DNA Test, their information is added to a database of possible matches. Even if the person that they are looking for has not undertaken a DNA Test themselves, it could reveal a close relative, cousins or other distant relatives – these are all great starting points and clues in their search, which they would not have had prior to undertaking a DNA Test.

Which Type of DNA Test Should I Take?

DNA Testing is a complex scientific study, however, don’t be put off by this. With ever growing popularity, a quick search online will bring up a myriad of possibilities with many companies and different types of tests. Let’s have a look at the types of DNA Tests available on the market first:

  1. Y-DNA Tests

The Y-DNA Tests can only be taken by males searching for their fathers. 

This is because the 23rd pair of chromosomes, also known as the sex chromosomes, are made up of the Y (male) and the X (female) chromosomes.  In a male, their 23rd pair is always an XY configuration, whereas in a female, theirs is an XX configuration. You inherit one of each of the chromosomes for your 23rd pair from each of your biological parents. If you are male, you inherited the X from your mother and the Y from your father – if you are female, you inherited an X from your mother and also an X from your father.

As females do not carry the Y chromosome, only males can take Y-DNA Tests to investigate their paternal lineage (results only follow the unbroken male blood line). In the context of searching for a birth mother and other female relatives for instance, this test would not be suitable.

  1. mtDNA Tests

mtDNA testing can be used by men or women to search for either parent although their effectiveness is questionable.

Mitochondrial (mtDNA) testing is the opposite to Y-DNA testing, in that while Y-DNA is passed down only from father to son, Mitochondrial DNA is passed down from mother to sons and daughters. However, mtDNA can only be passed on further by daughters, continuing the maternal family line.

As both males and females carry an X chromosome, it is possible for both to undertake mtDNA testing, which looks specifically into the maternal lineage. If you are specifically searching for your biological mother for instance, a mtDNA test could be considered – however, unless your biological mother has already been tested and her results are on the database, it would perhaps be more beneficial to cast the net wider to start with.

  1. Autosomal DNA Tests

Autosomal DNA Tests can be used by men or women to search for either parent and are often considered the most effective tests for doing so. 
The most common DNA Test that you will come across on the market, an Autosomal DNA Test, can be taken by both males and females and may provide you with DNA matches within 5 to 6 generations on both your biological mother and father’s side of the family. Autosomal DNA Tests are a way of analyzing the code that exists inside all of your cells and over 22 autosomal chromosomes – results that can be used medically or to identify your ethnic makeup.

An Autosomal DNA test is the most comprehensive and provides you with a much broader scope of possibilities than both the Y-DNA and mtDNA search, often identifying your second cousins and most of your third cousins. Although a pool of matches for further distant relatives is possible, the DNA links can be somewhat watered down and not necessarily as reliable as the closer matches – as you share less DNA with distant relatives.

If you are looking for as many clues as possible from a DNA Test result, Autosomal is by far the most popular choice and widest reaching.

There Are So Many Companies, Who Do We Recommend?

With DNA results, the number of matches that you will receive with distant relatives will vary from company to company. Each company has its own proprietary database of DNA results – therefore you will find some matches in one database that you would not necessarily find in another. For instance, AncestryDNA boasts a database of 20 million people and counting!

We encourage our clients to take more than one DNA Test for this reason, with Ancestry.com and 23andMe for example. By adding your results to more than one database, it increases the chances of finding a match and assists us in our search for your biological relatives.

Although extremely rare, some DNA testers have found their birth parents just through DNA results alone. In the many years of working to reunite birth families, these cases are few and far between, but not impossible. The closer the match to you, the more DNA you share and the more likely the result is reliable – it’s science!

How Do I Decipher My DNA Results?

If you find your DNA results to be too confusing and are struggling with where to begin, try messaging one of your DNA matches (often possible through sites like Ancestry.com). They could have already completed some crucial family history research that they’d be willing to share with you. 

If you would prefer not to make the initial contact yourself, talk to us at The Adoption Specialist, with our years of experience and knowledge, together with our Intermediary Service, we can guide you through your DNA test results.

When searching for your birth family it is important to remember that you are not alone. We’re here to guide and assist you through the process, every step of the way. 
For more information on how to find your birth family, fill out our Search Form or contact 949-610-2907 today!

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