Sunset at Gowanus Bay

Sunset at Gowanus Bay
Sunset at Gowanus Bay, Henry Gritten, 1851

Sunday, July 12, 2015

Brewer Branches on YFull's Experimental Y Tree

YFull is a company that analyzes data received from advanced Y-Chromosome DNA tests administered by various companies including the results for those who have taken the Big-Y* test with FamilyTreeDNA. To date, the Brewer DNA Project has had fifteen members take the Big-Y test. Most of these fifteen have taken the next step and have ordered an analysis of their Big-Y test data with YFull.** YFull's analysis of many individual tests allows them to identify SNPs that any one tested individual shares with others, and to identify SNPs that are unique to each tested individual. By comparing similarities and differences YFull has created what it calls, The Experimental YTree. This is essentially a genealogical tree of the male Y-Chromosome.

Members of the Brewer DNA Project who have taken the Big-Y test and have had analysis done by YFull have been placed on the Experimental YTree in the following locations (follow the links):

  • Descendants of Jan Brouwer, of Flatlands, L.I., defined as haplogroup I-Y7214. [Four descendants have been tested and analyzed].
  • Descendant of Adam Brouwer, of Gowanus, L.I., defined as haplogroup E-V13. [To date only one descendant (id:YF03732) has taken the Big-Y test. We hope for others to take the test so that this haplogroup may be further refined].
  • Descendants of George Brewer, of Brunswick Co., VA, defined as haplogroup I-Y15031. [Four descendants have been tested and analyzed].
  • Descendant of Ambrose Brewer, of Moore Co., NC and Hawkins Co., TN, defined as haplogroup R-DF13. [To date only one descendant (id:YF03733) has taken the Big-Y test. We hope that other descendants will follow].
  • Brewer Family originating in Gloucestershire, England ca. late 15th century, defined as haplogroup I-Y15575. [We currently have only one member of this family who has tested on any level with FamilyTreeDNA (id:YF03562). In other words, the tested individual does not match any other tested individual with the surname BREWER. We hope that others will be found who are interested and willing to join the project].
One feature of the Experimental YTree is that you can begin with the current defined haplogroup and work your way back up the Y-tree, one haplogroup at a time, to the beginning. On each of the linked pages above, you will find at the top, a horizontal row of haplogroups beginning with "Home" on the far left (black characters on white background). Starting with the furthest haplogroup at the right, you can use your cursor to click on each haplogroup which will take you back in time to the next branch back on the male Y-Chromosome Tree. In addition, estimates are provided for when each haplogroup was formed, and for a "time to most recent common ancestor" (TMRCA) for those in each group. For example, haplogroup I-Y15575 (the Gloucestershire, England family), was formed 4000 ybp (years before present), and the common ancestor our member has with the other individual in this haplogroup lived 3400 ybp. [Caveat: it has to be remembered that these figures are estimates, and that overtime, as more individuals are tested and their results analyzed and compared to others, these estimates will change. In addition, new defining SNPs for individual haplogroups will be identified, and eventually the YTree will have more branches and become more refined. Years before present, will also become better defined and more exact].

We would ask any of the other members of the Brewer DNA Project, who have already taken the Big-Y test, who have not yet submitted their data files to YFull for analysis and placement on the Experimental Y-Tree, to consider doing so. If you have any questions you can contact either of the administrators of the Brewer DNA Project (either Richard Brewer or myself) using the e-mail links found on the Brewer DNA Project's main page. In addition, we would ask other members of the Project, who have previously taken the Y-DNA tests that identify STR values, to consider taking the Big-Y test and to follow through with analysis at YFull.

*For more on the Big-Y test you are referred to some of the links found on the Genetic Genealogy Page.

**As of this writing YFull charges $49 for access to their results, billed after the analysis is completed. For a bit more on YFull please see Richard Brewer's, "An Application of FTDNA's Big-Y Test to Our Brewer DNA Project," pages 14-19.

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  1. As the individual I-Y15575, I don't think any of my male relatives will be testing. I certainly don't intend recommending them to. As yet, I haven't yet found a distant male cousin to agitate. My paper research suggests a long thin line of one or two males in each generation, with more Brewer males alive now than in any time since the late 15th C. My YFull data puts me at I1-Z138, which appears to be a west country group. Of course, my data stands somewhat outside the clusterings of other close matches whose names are Pugh, Williams, Jones, Thomas. My terminator at this date is A6539. YFull's date on I-Y15575 is 3300ybp. They have no date on A6539, but A6549 has a date of 1250ybp. It seems to me the TMRCA for I-Y15575 is somewhat earlier than A6549, probably closer to 3300ybp. but whether this means my ancestors were in Britain before the Romans, I have no idea.

  2. I have I-Y15575 just for your info..

    1. What is your surname? Are you a BREWER?


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