23andMe’s New and Improved Paternal Haplogroups


Science is dynamic and ever changing. As new research is published, theories get revised, and hypotheses retested. The field of genetic ancestry is no exception: The flurry of published research just in the last five years has been staggering, and we can now piece together the histories of many groups from nearly all parts of the globe. At the same time, a worldwide community of genealogists has seized upon this wealth of published research, combining it with their own genetic data to produce an even richer, more detailed human history.We want our customers to have the most current information possible, so our scientists and engineers have spent the last several months updating the paternal lineages, or haplogroups, for all of our (male) customers. This has been quite a task, involving many layers of analysis and quality control to meet our standards of precision and accuracy.   The end result is a more detailed understanding of paternal ancestry for our customers.The New TreeCustomers can find the 23andMe paternal haplogroup tree on the paternal line feature page.   It lays out the specific haplogroups for populations around the world, how they are related to each other, and how all men alive today can trace their paternal ancestry back to one individual who we refer to as the PoP (Poppa of all Poppas).   The organization of this tree is derived from more than 2,000 variable genetic markers, known as SNPs, on the Y chromosome. The particular combination of SNPs a man has determines which haplogroup his Y chromosome belongs to.Finding the Right TreeOver time enough additional SNPs are discovered, and there are enough revisions to the organization of other researchers’ Y haplogroup trees, that we must give our own a face lift to keep up. We used a variety of sources as a basis as we developed our new paternal haplogroup tree. We examined the published literature and spoke with experts in the field of Y chromosome genetic ancestry.   Perhaps most importantly, we used the wealth of information gathered from the International Society of Genetic Genealogy (also known as ISOGG).   This non-profit organization is run by genealogy enthusiasts who are passionate about discovering their family history through genetics. These enthusiasts, many of them 23andMe customers, have sifted through mounds of genetic data, both from the published literature and their own genetic profiles. The fruits of their labor are collected and organized in a haplogroup tree that is regularly updated at a high level of detail. ISOGG exists and prospers because so many genealogists are working together for a common goal.We have worked primarily with the December 2008 ISOGG paternal haplogroup tree as a basis for updating our own.   Even since then, some paternal haplogroups been updated significantly.   So for these rapidly evolving haplogroups, we used the May 2009 ISOGG paternal haplogroup tree as a reference. The end result is a very detailed and up-to-date paternal haplogroup assignment for each of our male customers.Your Paternal HaplogroupWhat does this update mean for our customers?   For many it means a change in their haplogroup assignment. That change may be slight, or it may be more substantial.   For other customers it means no change at all.   When examining your new paternal haplogroup, it is likely you will see one of the following differences:1) A more specific assignment:   Because the new paternal haplogroup tree examines many more SNPs than the original, we are able to give our customers more precise assignments. As a result, it is possible that your new haplogroup assignment may be longer and more specific than the original.   For example, customers who were assigned haplogroup J2a1 will now be reassigned to haplogroup J2a1a.2) A more specific and slightly different assignment:   This category of change is by far the most common affecting our customers, because the organization of the haplogroup tree has changed. Therefore someone’s new assignment may look similar to their old one, but it will be longer and/or slightly different. For example, a customer who was assigned to R1b1c may now be reassigned to R1b1b2.3) A completely new letter assignment: This is the rarest of the changes that will likely occur, and is also due to a reorganization of the paternal haplogroup tree over the past few years. For example a customer currently classified as K2 will now be reassigned to haplogroup T.It is important to note that your ancestry has not changed, only your haplogroup assignment. But because this update has allowed us to define many more haplogroups than we had originally, we can give even more specific information about our customers’ paternal ancestry.   In the coming weeks, we will be updating the summary pages for our haplogroups with this additional genetic history.
  • b farren

    does this haplogroup only work on males (since they carry the y gene?) or could a famale find out paternal info also?

  • Joe Kuehn

    I’m a 75 year old with Parkinson’s and numerous other infirmities who is interested in the 23 and me program. I’m amazed I’ve lasted this long. Perhaps a military career and 25 years of hiking, backpacking and a little mountain climbing has helped. Being a vegetarian put off heart disease for 20 years until it reared its ugly head a month ago when I had three stents inserted.

  • Hi b farren,

    Well, in a way the paternal line haplogroups only apply to males since, as you point out, only they carry Y chromosomes. But a woman can find out about her paternal ancestry through her male relatives. You can learn more in this Spittoon post: http://spittoon.23andme.com/2008/05/07/whose-y-to-use-paternal-ancestry-for-ladies/

    Men and women can trace their maternal ancestry back through their mothers, their mothers’ mothers, and so on, using mitochondrial DNA.

    More about all of 23andMe’s ancestry offerings is available here: https://www.23andme.com/ancestry/techniques/

  • I agree

    Men and women can trace their maternal ancestry back through their mothers, their mothers’ mothers, and so on, using mitochondrial DNA.

  • Susan

    Since women inherit an X from their fathers, isn’t it possible to get mtDNA information on the their father’s paternal line? I ordered a packet, but am curious how you can know for sure the maternal line information I get back is just from my mother and not also my father’s maternal line.

  • Hi Susan,

    With so many different types of DNA and inheritance, it’s easy to get confused! So let’s start with some of the basics:

    1) Women have two X chromosomes. They inherit one from mom and one from dad. Men have one X and one Y chromosome. Their X chromosomes always come from mom.

    2) Mitochondrial DNA is a whole other piece of genetic material, distinct from the X and Y chromosomes. It’s a little circle of DNA that has just a few genes on it that’s located inside organelles called mitochondria. Except for some *extremely* rare cases (I’ve only heard of one case), you only inherit mitochondrial DNA from your mother.

    The maternal line info 23andMe provides is based on mitochondrial DNA. So whatever your haplogroup is, you can be sure it is tracing your ancestry back through your mother’s line.

    But wait, there’s more! With 23andMe you will get information about your X chromosomes, which, as explained above, you got from each of your parents. In features like Relative Finder and Family Inheritance, you can use X chromosome information to learn more about your unique genetic history!

  • DaveXZ

    I understand ErinC’s posts the following:
    1) The maternal line is determined from the mtDNA and lonot from the 23 pairs.
    2) The paternal line is determined from the 23 Y.

    By the 22 pairs graphic of the Ancestral Painting, the 22 autosomes are determined.

    The big question I have is: What data presentation is determined by the 23 X for men and X’s for women?

  • Hi DaveXZ,

    I’m not sure I completely understand your question, but it seems that you are wondering where customers can see information about their X chromosomes.

    You’re right to point out there isn’t anything about the X or Y in Ancestry Painting. You can, however, look into what parts of your X chromosome(s) you share with others using the Family Inheritance feature and the Family Inheritance: Advanced Ancestry Lab. X chromosome DNA is also taken into account when finding relatives through Relative Finder.

  • Peter

    My Paternal haplogroup is R1b1b2a. I noticed that another member has the same 7 characters but with an additional 2 or 3 characters indicating more specificity. What does it mean that some Haplogroups codes appear to be more detailed than others but share most of the code?

  • Clara

    Peter I’m a R1b1b2a as well. It’s my understanding that those with designators past that are subclades that developed mutations that separated them causing new Haplogroups. At least that’s how I understand it.


  • Ben

    Around late June or early July I was R1b1b2a1a2f2, but now the f2 seems to have dropped off. Any ideas why this might have happened?

  • I decended Haplogroup A. There were no other alpha or numeric identifiers from paternal DNA test. What does this tell me besides the generic explanation?