Whose Y to Use? Paternal Ancestry for Ladies

gus.jpgOne of the most exciting parts of 23andMe’s Personal Genome Service™ is discovering your genetic ancestry. Suddenly your family tree has branches that reach back thousands of years into the prehistoric past.

At present, 23andMe customers can trace two branches of their genetic family tree – one that follows the all-female line on the maternal side (through mitochondrial DNA) and another the all-male line on the paternal side (through the Y chromosome).

Not all DNA is created equal, however: males have both mitochondrial DNA AND a Y chromosome, so they can trace both their maternal and paternal ancestry. Females, who have mitochondrial DNA but no Y chromosome, can trace only their maternal ancestry.

So how can females discover their paternal history? One solution is to ‘borrow’ the Y chromosome of her most immediate paternal ancestor – her father. A female can have her father send his own DNA sample to 23andMe, then examine his Y chromosome as a way of understanding his paternal ancestry and her own.

But what if a woman’s father can’t or won’t share his DNA? By sharing 23andMe accounts with the right male relative, a woman can still discover both her maternal and paternal ancestry.

So whose DNA can a female customer use, besides her father’s? It could be anyone who shares his Y chromosome – her brother, paternal uncle (father’s brother), or even paternal grandfather (father’s father). The chart below illustrates some of the possibilities in one woman’s family tree; male relatives who share her father’s Y chromosome are depicted in blue.

You may look at the chart and ask: Why not her son’s Y? After all, he’s a male relative, too. But even though a mother shares 50% of her genes with each of her children, only fathers pass Y chromosomes to their sons. So any examination of her son’s Y chromosome would yield not her father’s paternal history, but her husband’s.

The woman whose family tree is shown here (“Me”) could determine her paternal ancestry using the Y chromosomes of males who are colored blue.

  • Scott23H

    Her ancestry is a mix of both her father and her mother. Although we cannot easily identify what came from her father, there are ways to do that. If her mother were to test for instance she could then look at split view in the ancestry composition tool and see what ancestry came from her mother and what came from her father. The reason testing her son wouldn’t help is that the Y chromosome is passed on from father to son. That traces the paternal line. So her son didn’t get his Y from her father but from his father and his father’s father.

    • kitty

      Ok, but then what if the woman who has the father who was adopted but died also has no sisters and her mother is dead also ? Then she has only herself to take the test to find out what her father’s ancestry was, wouldn’t there still be a way since she would have half of what he was in her genetic pattern ?

      • Scott23H

        Hi Kitty,
        That will be much more difficult. It will take using other information she may have about either her mother or father. It may be that she can look at her DNA Relative matches. Some of those will be from her father’s side. Looking at how those matches cluster and the ancestry of those individuals may help. Again it will take some triangulating of information.

  • Maxwell98761

    I am another daughter interesting in finding more about her father’s genetic history under seemingly impossible circumstances. My question is how far down can you go in a male line that is parallel to my fathers line to get reliable dna paternal results? (my grandfather’s brother’s). My father and his brother only had daughters. I would only possibly have dna from my grandfather’s brother’s line of males. My father was born when my grandfather was 40 and my grandfather was one of the youngest of 12 and according to family history that I have, most of my grandfather’s brothers died when my own father was in his 30’s. To make matters worse, I was born when my father was almost 50. An available male cousin from my grandfather’s brother’s would probably be at least 3 (maybe 4) generations down the line. Is that too far removed to produce reliable and revelent results?

    • 23blog

      Just to be clear, you get DNA from both sides of your family, but if you are woman you need a male relative on your paternal side to be able to trace your paternal line.
      So that means you will get DNA relative matches from both sides of your family. The issue of identifying which side of the family a match comes from is harder however. You’d asked about whether you had your paternal grandfather’s son’s son tested whether that would be helpful. Yes that would give you your paternal haplogroup. As long as you can trace that directly through the male line to a common grandfather you could indeed use that to identify your paternal haplgroup. Here’s a link to more about linking a relatives paternal haplogroup. (https://customercare.23andme.com/hc/en-us/articles/202906940-Linking-a-relative-s-paternal-haplogroup)

      • Maxwell98761

        Thank you so much for your help!

  • caren

    Can I use my sister’s son to our fathers grandfather bloodline ?

    • Scott23H

      The short answer is no that wouldn’t help you.

      For females, if a male relative such as your father, brother, paternal uncle or paternal male cousin were to be genotyped then you would be able to infer your own paternal haplogroup information from his. If your brother were to provide a sample, you would learn your maternal haplogroup as well as your paternal haplogroup.

      However, if your father or father’s brother were to provide a sample, you would learn your paternal haplogroup, but not your maternal haplogroup since he does not share your mother. If your biological father participates, you can link his paternal haplogroup to your profile so that it will appear on your own Paternal Line page.

      Haplogroups are one small part of your ancestry analysis. The 23andMe Personal Genome Service provides you with information from all branches of your family tree using your autosomal DNA.

  • Angela Sherman

    My question I hope isn’t too confusing. I understand about getting my paternal and maternal heritage. However I am wondering isn’t my mothers paternal line important to my ancestry too? Her being female also would mean that she didn’t get her fathers Y correct? Doesn’t that mean that I wouldn’t get to understand the heritage of my maternal grandfathers all the way down the line unless I had my grandfathers,or maternal uncle’s dna? My grandfather has passed so does that mean I would have to get my maternal uncle to give me that information?

    • 23blog

      Hi Angela,
      Your initial questions was a little confusing, so apologies for not responding sooner. The simple answer to your last question is no. You would still be able to see the ancestry contributions from both your maternal and paternal side. You will also be able to get DNA Relative matches from both sides of the family.

      The analysis of the 22 autosomes is the same for women and men and provides the same information and level of detail. For each pair of these chromosomes one comes from your mother and the other from your father: two copies of the same recipe with slightly different ingredients. The autosomes are what we use to determine your DNA Relatives, your Ancestry Composition results, your health and trait reports, and many other features. The great majority of our features are based on the autosomes.

      However, since men and women have different sex chromosomes, there are some small differences in the information they will receive. For example, men will only display a single X chromosome in features such as Ancestry Composition, while women will have two.
      Since women have two X chromosomes instead of an X and a Y, the 23andMe Personal Genome Service does not directly provide paternal haplogroup assignments for women. The paternal haplogroup is traced through the Y chromosome, which women do not inherit.

      • Angela Sherman

        Thank you for thoroughly answering my question. I again apologize for the confusion.

        • 23blog

          Glad to help Angela.

  • tajma

    Can i test a half brother to see if his father is my father and if we matched hat would the result look like

    • 23blog

      The answer to your question is yes. If you share the same father than getting your half brother to test would allow you to learn about your patneral haplogroup. It will also help make clearer who of your DNA Relatives are match through your paternal line and who is matched through your maternal line.

      • tajma

        But would our relationship show ss 1st cousins or siblings

        • 23blog

          If should show as predicted half siblings or as another close relative.

  • Katherine

    I have a question about ancestral composition. I am female. Does the composition show both father and mother’s contributions? Thank you!

    • 23blog

      Yes it does, but we can’t identify what came from your mother and what came from your father without additional information. If one of your parents is tested then we can show a “split view” showing what came from each parent. Here’s a link to more information on ancestry composition’s split view: https://customercare.23andme.com/hc/en-us/articles/202906820-Enabling-Split-View

  • Amy

    My biological father is no longer living, nor is my paternal grandfather. Dad had no brothers. I am one of four girls, so I have no brothers. I did my testing through 23 and Me before knowing that you can’t trace the paternal line if you don’t have DNA from the father, paternal uncle or brother. I assume there is absolutely no way for us to trace our paternal side?

    • 23blog

      Hi Amy,
      It’s true that you won’t be able to get information about your paternal haplogroup, but you can still learn a lot about your ancestry including your father’s ancestry.
      It will be harder to figure out what came from your father and what came from your mother, but your results reflects the contributions from both your parents. So your ancestry composition and the DNA Relative matches include contributions from both your mother and father.

      Haplogroups are one small part of your ancestry analysis. 23andMe provides you with information from all branches of your family tree using your autosomal DNA.

    • Trixanne

      If your paternal grandfather had any brothers and they had sons then you might be able to get your answer that way. Easiest way to think about it – any male cousins/second cousins/etc with your fathers last name? If so then they may be the link you need to find your paternal haplogroup. Try using your DNA to seek out relations with your fathers last name if you don’t know any yourself.

  • 23blog

    The answer is yes. Her Ancestry Composition would show contributions from both parents. The difficulty for women is that they can’t see their paternal line, so in looking at her ancestry composition it would be hard to figure out what contributions are from her mother and what are from her father.
    For more information on this go here: https://customercare.23andme.com/hc/en-us/articles/202908000-Do-men-and-women-receive-different-information-from-23andMe-

  • 23blog

    I’m not sure I’m following exactly what you’re asking but I’ll attempt to answer your question.
    Your paternal line traces your father’s,father’s father etc, while your maternal line traces your mother’s mother’s mother etc. What you’re asking about is your father’s mother’s father. You can’t really find your out about your dad’s maternal grandfather’s paternal line. However your DNA relatives matches and our ancestry composition results include all contributions on your family tree.
    Having your father test would improve your results and if he shared with you, you could learn about both his paternal and maternal line.
    Here’s more about paternal and maternal lines:https://customercare.23andme.com/hc/en-us/articles/202906930-What-is-a-paternal-haplogroup-

  • Holly Fischer

    Hi, my father and brothers are all deceased. My first cousin once removed is alive and willing to be tested to help me out. He was my father’s first cousin. Their fathers were brothers who shared the same father. Would this relationship give me the correct yDNA information. I am a member of 23andme. Thank you.

    • 23blog

      Hi Holly,
      The answer to your question is, yes. If he was your father’s first cousin and their fathers were brothers who shared the same father then they would have the same paternal haplogroup.

    • Jane

      Hi Holly – Im looking for a Holly that I have as a match on 23andme. If on the small chance its you .. please sign on and view our exciting results :) I sent a message. Thanks!

  • 23blog

    Finding your maternal grandmother’s paternal line would require finding family on her paternal line. So if she had brothers then testing any of your cousins who are on that male line.

  • 23blog

    You will get matches from all branches of your family tree. The difference for women is that we cannot report their paternal haplogroup’s unless they have a male relative on their paternal line tested. This is because women have two X chromosomes instead of an X and a Y. The paternal haplogroup is traced through the Y chromosome, which women do not inherit.

  • Faith

    I have a question I hope someone will be able to answer … my father has passed on and I trying to find out if he is my biological father but both of his parents have died and he has no brothers but I found his aunt and she willing to do a DNA teat would I be able to find out that way or not ?

    • 23blog

      If your father’s sister is alive and she tests that would be one way to determine if he is your biological father. If he is then she would share about 25 percent DNA with you. If he is not your biological father you would not share any DNA with her.

  • 23blog

    A little bit more distant in terms of relation, but that could help you. This would be your great Aunt, correct? So the connection is through your father’s line. The only other consideration if you find that you do not share any DNA with her. First off, there are a few other potential “non-paternity events” that could explain why that is. In other words, perhaps the non-paternity has more to with her parentage than yours. And then there’s your father’s parents. Those are two points where the line connecting you to her could be broken. And of course there’s your father which is the other point where that connection could be broken.

  • 23blog

    If you both opt in to show close relatives and he is your biological father, then yes he will show up as your biological father.

  • Jasmine W

    I’m currently searching for my father and his family that I’ve never met. I don’t have any info about him or his family. Just curious, would it be easier for me to find my paternal linage if my mother tested also? If not, are there any other ways to go about it?

  • CeCeZee

    They have a saying in the black and mixed race community,you are what your father is. Regardless if you are male or female. Which I never liked that term. But now I will always say: Females have there mothers genes and boys have there fathers.

    • Sha-Sha Downing

      Boys have the genes of both their father and mother. Girls only have the genes of their mother.

      • 23blog

        That is not correct. Everyone inherits half of their DNA from their mother and half from their father. What is different is that women do not inherit a Y chromosome from their father. So there is not a continuity in the paternal line of inheritance for girls. But daughters are a mix of both their mother’s and father’s DNA.

  • Maria Del Carmen Aguirre

    Hi, I wonder why do I have a paternal line?? It appears to be T, I don’t understand since I am a woman.

  • 23blog

    There’s some detailed information about this in our FAQs. Here’s a link: https://customercare.23andme.com/hc/en-us/articles/202908000-Do-men-and-women-receive-different-information-from-23andMe-

  • 23blog

    Hi Kitty,
    Your ancestry composition is a mix of 50 percent your father and 50 percent your mother. If you know about your mother’s ancestry and it was distinct from your father, you might be able to figure out more about the mix of your father’s ancestry.

  • subroo

    To be clear, if I do not have a sample from my father side of the family (Y) will what I get from his side be from his mother, and perhaps her mother etc? This is really disappointing because I was hoping to have questions answered from his side?

    • 23blog

      You will still get information about yourself that includes what you inherited from your father. So your mix of ancestry in the the Ancestry Composition will be the mix you inherit from both your mother and father. The issue is that it will be harder to identify what came from your mother and what came from your father. You will also still be connected to DNA relatives from both your maternal and paternal side of the family. But you will not be able to easily identify which side of the family those DNA Relatives come from unless you have some additional information that will help you. So for instance, if your mother and father had distinctly different ancestry, say one was Ashkenazi and the other had ancestry from the UK, that would help you figure out which side of the family a DNA Relative was from because you could see the ancestry of some of your matches. You could also look at geography and surnames that are included in your DNA Relative matches to help you figure that out.

  • 23blog

    Hi Rebecca,
    Either would be good, but having your father tested would allow for you to see specifically what came from your mother and what came from your father. It would also allow you to see your paternal haplogroup.

  • 23blog

    No because they do not share the same father so he and his half brother do not have the same paternal line. If he had a half brother with the same father you would.

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