DNA Testing To Identify a Birth Parent

Diahan Southard

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Do you have an unknown birth father OR mother? Here’s what to do to use DNA testing to identify your unknown biological parent, or at least to learn more about that parent’s family tree.

If you have one known parent and one unknown parent, you may be able to use a pretty straightforward process to identify your unknown parent, or at least to learn more about that parent’s family. I’ll explain this process using a real scenario, with details changed for privacy reasons. But you can follow these same steps yourself, adapting them for your own situation.

DNA Testing to Find a Birth Father or Mother

I know a woman—let’s call her Lora—who is looking for her birth mother. Lora was raised by her biological father, but all she knows about her birth mother is that she was working with her father at a Ford Motor plant in Detroit 80 years ago when Lora was born. The circumstances were such that Lora’s mother was forced to give Lora to her father to raise.

Lora guesses that her birth mother is probably long since deceased, but she’d still like to know who she was. She decides to take an autosomal DNA test.

Getting Started

DNA testing identify unknown birth parent mother father tree ID.pngLora tests at AncestryDNA because its huge testing pool increases her chances of connecting with close DNA matches. Since she knows her birth father’s family well, she researches and creates an online family tree for him on Ancestry.com. On this tree, she identifies her birth mother only as “birth mother,” with a residence in Detroit 80 years ago. (Here are more tips on creating the best online tree for your DNA profile.)

She Gets Her DNA Test Results…

When Lora receives her DNA test results, she links them to her tree. Next, she goes to her DNA home page and selects the option to View All DNA Matches. Since this is an autosomal DNA test, her matches include relatives on both her mother’s side and her father’s side. She needs to separate these matches from each other.

DNA testing identify unknown birth parent mother father tree create custom group.pngThe easiest way to do this is to identify the matches on her father’s side (which she knows something about) and set them to one side. In anticipation of this, on the top of her match list, she clicks Groups > Create a Custom Group and creates a group called “Mom’s side.” She repeats this process to create a group called “Dad’s side.” She chooses different colors to identify each group.

Next, Lora looks for the closest possible DNA match she can recognize on her father’s side. Ideally, she would have her father, her father’s sibling, or her own sibling by that father also test at Ancestry. But she doesn’t have that option, so she scans down the list of usernames and photos for familiar names and faces. (If she doesn’t find a close match here, she’ll use the Search box to search for his surname and his mother’s maiden name in both the Match Name and Surname in Matches’ Trees boxes, as shown below. Lora can widen this search to include more of his ancestral surnames, too.)

DNA testing identify unknown birth parent mother father tree search.png

Lora identifies a close DNA match on her father’s side: a first cousin. She clicks on the box Add/Edit Groups next to that match’s username and adds him to the “Dad’s side” group.

Click to read this related article.

Click to read this related article.

Then, on that match’s profile page, she selects Shared Matches. This shows her all those who have tested at Ancestry who share DNA in common with both herself and this relative of her father. Lora goes down the Shared Match list, adding each one to the “Dad’s side” group by using the option to Add/Edit Groups to the right of each of her close matches (4th cousin range or closer). When she finishes, she returns to the main match page. All close matches remaining without the “Dad’s side” label are added to the group “Mom’s side.”

(Note: if Lora’s birth parents were genetically related, this process won’t work. She’s beginning with the assumption that they were not.)

Working with an Unknown Birth Parent’s DNA Matches

Now that Lora has separated her birth mother’s DNA matches from those belonging to her father, she can focus on the former. Under Groups, she selects the Group “Mom’s Side,” and she begins reviewing this match list.

It is possible Lora will see a very close relative, such as the birth mom herself or a half-sibling, which Ancestry can identify by the genetic distance between them. But it is more likely her closest matches will be within the range of first to fourth cousins, which turns out to be the case. Only a few of them have trees posted and only a couple of them respond to messages she sends.  She feels discouraged and takes a break from the search for a few months.

But not forever. And it’s a good thing she comes back to it, because meanwhile, another important DNA match has popped up….

Read what Lora discovered—and what her next steps should be.

Tips for YOU

If you, like Lora, have DNA matches that you want to contact, then our free guide to contacting DNA matches is a must! We’ve put together our best tips into one free download, just for you!

Show me that free guide


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<a href="https://www.yourdnaguide.com/author/guideyourdnaguide-com" target="_self">Diahan Southard</a>

Diahan Southard

As founder and CEO of Your DNA Guide, Diahan Southard has been teaching people how to find family history answers in their DNA for several years, and she's been in the genetic genealogy field since its infancy. Diahan teaches internationally, writes for popular magazines, consults with leading testing companies, is author of Your DNA Guide–The Book, and producer of Your DNA Guide–the Academy, an online learning experience.


  1. Stephen C Stenger

    I did the 23andMe me about ten years ago. I kept up with there info fora long time and never got anything from it. They did not offer any form of help. They would send 5th and 6th generation, but the only thing I was interested in was finding my father. I could not recommend them at all. Steve Stenger (Stang-r@juno.com)

  2. dar

    Stephen, you do realize that if no closer relatives than 5th or 6th cousins take a DNA test then 23andMe will not have any results for you.

  3. Scott Morse

    Great article. Your outline is very similar to the approach I used. Though my efforts (20 years) in discovering my biological father have, thus far, been unsuccessful, I’m fully aware of the waiting game side of the equation. I think that a large segment of the folks searching unsuccessfully for an "Unknown" often have unreasonable expectations. To those folks I’d say that all is not lost. As the popularity of DNA testing grows so will the DNA database. Sooner or later, that elusive donor will pop up. Thanks for a well written affirmation.

    • Diahan Southard

      Thank you, Scott, for sharing your experience, it is so valuable! You are so right, your patience will pay off eventually.

  4. Cherie Ohlsson

    Diahan, If I take all the matches to my known match on the mother’s side, it had about 10 matches. That left thousands of leftovers that some of which must be part of the mothers side. If I take all the leftovers and put them on the father’s side aren’t I misleading myself? Should I find shared matches with each of the ten people and add more people in the mother’s list? and continue this way until I don’t have any more shared matches for the mother’s side?

    • Diahan

      This article is specifically talking about finding birth parents. So it is assuming that your known match on your known parent’s side is a very close match. A half sibling or a first cousin. Your situation is different because your known match is more distantly related. And yes, keep going in the DNA Skills course and you will see in Lesson 3 I talk about expanding your network.

  5. Victoria Limback
    1. I have a similar case but more complicated. My biological birth mother is Asian – either Korean or Japanese and I was born in S. Korea. My father was white American born in USA and he brought me to USA from S Korea on his USA passport in 1955. He was an only child who died in 1979 before DNA testing was available. His parents all dead.

    2. I have no birth certificate and cannot get one because:

    A. I do not know whom my biological Asian mother is;

    B. If Korean, per Korean USA embassy – only male Korean citizens can and could report a child’s birth if born in Korea (husband, uncle, make cousin, brother or son). My father was an USA citizen;

    1. My birth name is given to me by my biological father and is English/French/German names and in that order too (1st name, middle, & last name).

    2. I have a lot of problems with wrong info out there on me on the Web and with various places, even DNA & genealogy databases have obtained and stored incorrect date if birth, addresses and relative info on me. I know this because I did pay for My Heritage DNA testing but then cancelled after finding it’s website on me disregarded the info I had provided as correct and replaced it with INCORRECT DOB, RELATIVES, & ADDRESSES from their databases on file even before I joined and paid for DNA testing (that’s main reason I cancelled. I offered to send proof of my name & DOB and other confidential documents by mail but was told an Israel address to send such was only address so I refused to send my confidential life records out of the USA and therefore again cannot straighten out wrong DOB etc on me.

    3. I have had my driver’s license and IDs stolen in the past several times from home burglaries and thefts and from people using my name to get credit cards, money etc illegally using my name. Luckily in the State if CA where I currently live, as long as you know your driver’s license number and your CA DMV photo matches what is in the CA DMV record database, you can get a replacement driver’s license (or it used to be that way and how I got my IDs replaced after thefts).

    4. But since the 9/11/2001 terrorist incident, credit bureaus and most govt agencies require a birth certificate which I don’t have and I can’t get – since birth certificates are based on biological mother info, so
      the dilema and need to know biological mother.

    I’ve tried to get help from Legal Aid,from Law Centers etc but they don’t help.

    1. The worldwide databases have limited Asian DNA databases and my father’s other children born in the USA with different biological mothers refuse to help me or do any DNA testing to prove at keast we have the same father.

    2. If USA did birth certificates also by biological father instead of by mother only, I wouldn’t have such problems trying to correct wrong DOB, addresses etc out there on me whether from ID fraud/theft(s) etc.
      I could have Medicare medical insurance and my retirement would correctly reflect past earnings and I wouldn’t have to keep fighting the wrong DOB and info out there on me.

    3. My name and correct DOB are shown in Immigration papers my father filed in Michigan in 1965 when I was 5 – but Immigration wouldn’t complete the process saying the Immigration Dept required a Marriage Certificate that my father married my biological mother & also needed a birth certificate for me to complete the Immigration filing process; Impossible things for my father to produce.

    4. I also know my correct name and DOB because such are listed in the State of Michigan juvenile court records, as I was a Ward of the Court & State of Michigan after my father divorced my step-mother in 1965.

    So how can someone with my complicated life get help thru DNA and what types can I take if no half- sibling will help ?

    • Diahan

      I hear you. It sounds like you have been walking a very long road. It shouldn’t be this hard to find out more about yourself.
      The great thing about DNA is that no one can overwrite it or change it. It is a record of your heritage and can be used to learn more. So testing with one of the five major DNA testing companies will provide you with information about your family. You will likely have many more DNA matches to your dad’s family, but that may change in time as the databases get bigger.
      Here is a quick guide to the DNA testing companies available, hopefully that can help you get started: https://www.yourdnaguide.com/ydgblog/2020/8/6/which-dna-test-company

  6. Christine

    I don’t know where to go. I know my birth mother and her side of the family. I only know the state where they lived when she conceived and that my biological father lived next door. Apparently, he was Native American, married and had 9 other children. My mom will not speak of it and my grandparents passed before I ever got an opportunity to ask. My aunt & uncle were too young to remember all the details. My birth certificate has my mother’s husband listed as my father and I was born in a completely different city & state. I was in my 20’s before I was told my dad wasn’t my dad. Where do I even start? I don’t have a ton of money to spend on tests & kits but I would just like to know before I die where I came from. I just need some guidance.

  7. Tiffany Wingo

    Where to go all I have is names and dates of tragic conception and known whereabouts I know my Mother but I don’t know my Father which DNA test will help me !

  8. Derek Thom

    I’m still struggling to find out which, if any DNA test, will help me follow the male lineage of my maternal side. I have a brick wall with my maternal 4 x great grand father and no male maternal side source of DNA to test with. Any suggestions?

    • Diahan Southard

      If you have a grandparent or parent (or great aunt/ uncle or aunt/ uncle) from that line that can take a test, your best bet would be for that person to do an autosomal DNA test. After that your next best bet will be to find a direct male descendant (if there is one) of the ancestor your are looking for and have them take a YDNA test.

  9. Sandra

    I would like to learn if the people listed on my birth certificate are my real parents. Each year 28,000 babies are sent home with the wrong parents. Would my parents also have to have a DNA test? They are dead now. They were both wonderful parents and I am grateful for that, but for some reason I never felt part of the family. I am taller than my own father and brother (I am a woman). I don’t look like my sisters at all. I need advice on how to learn more about my heritage and possibly my parents. Thank you.

    • Your DNA Guide

      Hi Sandra – You don’t need to have your parents tested. You might be able to learn if your parents are your birth parents simply by testing yourself. If matches appear with people you know in their trees, then you will know you are related to your parents biologically. If you don’t recognize anyone in your match list, you could do something called target testing. Ask a known maternal cousin and a known paternal cousin to test as well. If they do not show up as matches, then you will know that you are not biologically related to your parents. I hope that helps!


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