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The Big-Y matching program is robbing you of your correct matches.

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  • The Big-Y matching program is robbing you of your correct matches.

    About 60 to 75 percent of my members who have taken the Big-Y test have no Big-Y matches, even when they do have matches. Not even their exact terminal sub-clade matches. About 10 percent have incorrect Big-Y matches. I have written to FTDNA multiple times about this problem. FTDNA tells me that the algorithm that they use is "Big Y-500 matches must share a terminal SNP within four steps as well as have no more than 30 mismatching SNPs"

    The problem with this is FTDNA includes all SNP's that define the sub-clade plus not-named SNP's plus unreliable SNP's. If you have more than 30 not-named SNP's you will never have any Big-Y matches. There are many sub-clades that have 10 to 20 SNP's that define the sub-clade, so added to the not-named SNP's will push you over the limit.

    I would recommend that all Big-Y testers complain to FTDNA about this. Why spend $400 to $600 and receive no matches that are impossible to contact?

  • #2
    Originally posted by Ericjle View Post
    About 60 to 75 percent of my members who have taken the Big-Y test have no Big-Y matches, even when they do have matches. Not even their exact terminal sub-clade matches. About 10 percent have incorrect Big-Y matches. I have written to FTDNA multiple times about this problem. FTDNA tells me that the algorithm that they use is "Big Y-500 matches must share a terminal SNP within four steps as well as have no more than 30 mismatching SNPs"

    The problem with this is FTDNA includes all SNP's that define the sub-clade plus not-named SNP's plus unreliable SNP's. If you have more than 30 not-named SNP's you will never have any Big-Y matches. There are many sub-clades that have 10 to 20 SNP's that define the sub-clade, so added to the not-named SNP's will push you over the limit.

    I would recommend that all Big-Y testers complain to FTDNA about this. Why spend $400 to $600 and receive no matches that are impossible to contact?
    I'm not sure I agree that it is robbing you of your correct matches. In my case if it permitted a whole whack of matches they would all be inaccurate. I have two matches who are downstream of my terminal SNP and we have an estimated TMRCA of ~1,800 years! Getting a whole load of matches can be misleading and can send people down the wrong path, especially with Big Y which is based on far older mutations. Not-named SNPs are actually unnamed SNPs (which means NOVEL, new), not yet placed on the tree. Some of these are not shared with other people and that is an important distinction. As unnamed novel SNPs can be used, with further testing of potential relatives, to determine specific lineages and subdivisions of haplogroup branches.

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    • #3
      Originally posted by spruithean View Post
      I'm not sure I agree that it is robbing you of your correct matches. In my case if it permitted a whole whack of matches they would all be inaccurate. I have two matches who are downstream of my terminal SNP and we have an estimated TMRCA of ~1,800 years! Getting a whole load of matches can be misleading and can send people down the wrong path, especially with Big Y which is based on far older mutations. Not-named SNPs are actually unnamed SNPs (which means NOVEL, new), not yet placed on the tree. Some of these are not shared with other people and that is an important distinction. As unnamed novel SNPs can be used, with further testing of potential relatives, to determine specific lineages and subdivisions of haplogroup branches.
      Pretty much the above, I'm only interested in results I can find paper trails for. So getting a match list almost entirely populated by persons with common ancestry dating back to more than 500 years ago is not particularly useful, given most families are going to be hard pressed to even reach the 17th Century on paper alone(with a number of wishes along the way).

      Where those matches are "slightly useful" is when they all seem to point to a common (narrowly defined) geographical area, if they're lucky enough to have sufficient reliable information to point to where the line was in that more distant time-frame.

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      • #4
        I feel the pain of the Ericjle, and glad I saw his post. While another service (YFull) gives me a terminal that matches me with someone who is not a Y match and is many thousands of years back for common, there has to be a middle ground. FTNDA have altered my terminal and my wife's uncles terminal to what appear to be very novel or private values. It would be great to know if anyone else has them, or if they came up within 300 years, but by the same token, where are the age estimations or explanations for any of the SNPs assigned by FTDNA? I am in the dark about values that are not recognized on ISOGG, especially if they are prefixed BY.
        I learned today that after goading by me, a known cousin of mine took advantage of the sale and is the second of my "line" (after me) to do Big Y, he comes down from a man who is probably the brother of my ancestor from flourishing in 1771 Surry Co North Carolina. We have very strong paper-trail genealogy and his GD is 1 from me with 111 STRs, and our common ancestor is at least 6 gens back, So in March or so, I will see what he shows for Big Y-500 STR Differences and matches. I am also encouraging him (when he gets results) to upload to YFull, because I think everyone should have an alternate interpretation of something that is this expensive and (typically) far removed from the Y STR tools and grid. By my estimation, he would have to be a match, as I used to have when my terminal was I-A1890. I find it very difficult to promote this test among my 50 members because of what Ericjle is writing about, the almost total disconnect between Y STR and SNP testing. I know why it is there, but there seems to be little effort on the part of haplo admins to bridge the gap between their goals and mine, which, as bartari206 writes, is to see meaningful groupings to support genealogy, not with some SNP match that serves to disconnect me from people that I know are my patrilineal cousins.
        Last edited by clintonslayton76; 23 December 2018, 05:04 PM. Reason: spelling corrections

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        • #5
          The posts above made some good points, but what I am referring to is people who took the Big-Y test and have NO matches, when they do, even their exact terminal sub-clade matches. It is impossible to contact them to find out if they are related. I know of over 10 known exact terminal sub-clade matches who have not joined any projects. So you can not find them that way. They don't know to join, because they have no matches.

          As far as the Haplogroup Admin., most of the Haplogroup Projects are so large that its impossible for the Admin. to individually help every member with their goals. It took me 3 months of appeals to get my small Haplogroup project started. Now with 100 members we are now down to genealogical timeframes, 7 branches are down to 50 to 300 years ago with Big-Y. We have solved several adoption and NPE cases.

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          • #6
            As I perhaps did not make clear, I have 15 Y STR matches to paper-trail males and NO Big Y matches with anyone. That is why I will be looking at a cousin's Big Y500 results, to test your theory. If FTDNA's Big Y matching criteria is too specific, it should be obvious when patrilineal KNOWN relatives are tested.

            I was advised by three haplo admins of three different projects (and repeatedly), that spending $ on testing my Y STR matches for Big Y was a waste, because they would by definition still match their Y STR cousins. They also responded to individual queries from members the same way: they said only ONE member each of my largest groupings (I-M253 and I-P37.2) needed to test SNPs because cousins would learn nothing new from the expense.

            Yet another admin advises men to test only 12 STRs and then spend their money on individual SNPs, which I find to be hare-brained from the point of view of a genealogical surname project, but sensible if the only goal is to save money and get the most general haplogrooup assignment. As stated by bartari260, our goal is to plausibly corral the patrilineal lines found in documentation, not to find out which continent our ancestors lived on 30,000 years ago. I am aware that those time-scales are more frequently seen from SNP testing, but have been assured by every popular treatment on the subject (Bettinger, Dowell) that the more men do the sequencing, the more likely are historical-time SNPs to be discovered. I hope they are correct. But as I infer from the original complaint, explaining this to potential samplers when FTDNA comes back with very specific terminals that make for non-matches makes it a hard sell.

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            • #7
              Originally posted by Ericjle View Post
              The posts above made some good points, but what I am referring to is people who took the Big-Y test and have NO matches, when they do, even their exact terminal sub-clade matches. It is impossible to contact them to find out if they are related. I know of over 10 known exact terminal sub-clade matches who have not joined any projects. So you can not find them that way. They don't know to join, because they have no matches.
              Until there is evidence to support a higher than currently expected mutation rate in Y-DNA SNP's, if you're more than 30 SNP mutations removed from your terminal SNP Match(which I understand is the cutoff at present for BigY), you're probably not related in the past 500 years at the earliest.

              Even going with 5 generations/century and 1 mutation per generation(and no regressions), for both sides of the match. Your earliest connection would be 300 years before the Y-DNA tester was born. But IIRC, ISOGG is seeing indications that typical average generation for men is closer to 33 years, not 20. 15*33=495 years and considering that the average Y-DNA mutation rate is expected to be a little bit slower than that...

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              • #8
                bartarl260 The 30 SNP differences includes all the SNP's that define the sub-clade plus all the Not Named (Novel Variants) plus unreliable SNPs. I proved this to FTDNA, they replied to me for comments to the IT team. Many people have over 30 Not Named (Novel Variants), so they will never have Big-Y matches.

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                • #9
                  clintonslayton76: What is your terminal sub-clade name? I may be able to find your Big-Y matches, by going to FTDNA projects or better by going to the new phylogenetic tree.

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                  • #10
                    "Robbed" seems too strong a word, but it is clear that FTDNA could do a much better job of putting the Big Y results into a meaningful context. As far as I know, my best matches are still likely a few hundred years in the past, so they are nothing to get excited about from a genealogical viewpoint. They do, however, demonstrate clearly that my McCoy family is not connected with any other McCoy family that has been tested, and that is a very useful piece of information from Big Y. But I obtain that context from Y Full and from the Big Tree, not from FTDNA.

                    The desired context should not be constrained by a fixed number of SNP's, but rather, and if at all, by some number of matches, displayed in such a way that it is clear what sort of distances separate them based on their respective locations in the haplotree, with also an option to display STR data and STR distances. In other words, the display I want to see should answer the question, "what does my haplotree neighborhood look like, and who are my neighbors?" The Big Tree does most of that very well, by the way!

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                    • #11
                      Ericjle, If I understand your question correctly: FTDNA gives me the path: I-Z2535 >CTS10937 >Y3153 >A1890 >F1997, and YFull gives me I-A1890 as terminal. I used to have matches before FTDNA went down this path. As stated by others, they were not particularly meaningful, because FTDNA gives no YBP values, but I was down to a 2300 YBP from YFull/ISOGG, and hoping to see some refinement instead of losing all contact with even distant men. I was fortunate to retain the contact information for a Swedish gentleman who has been a lively correspondent, common ancestor within 20 centuries or not.

                      Any help would be appreciated, I am writing a book about the fundamental surname findings for more than three lines, and writing (and self-editing, a foolish enterprise) takes most of my energy these days. It is not clear to me how you would be able to do this, since my haplo admin states that FTDNA's newest terminals subvert the process.

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                      • #12
                        clintonslayton76 Your statement “but have been assured by every popular treatment on the subject (Bettinger, Dowell) that the more men do the sequencing, the more likely are historical-time SNPs to be discovered” This is absolutely true. As an example, I recruited two distant cousins to test Big-Y and went from 2800 ybp to 175 ybp. This created a new sub-clade, that found two more Big-Y matches that created two more sub-clades above me.

                        YFull has you
                        -A1890A7425 * A1890 * A1892 formed 3000 ybp, TMRCA 2900 ybp with no sub-clades below,that match with Sweden
                        There is a difference between YFull and FTDNA is because the other persons probably didn’t join or there is a difference between reliability of the SNPs between the two companies.

                        At 2900 ybp you probably have a lot of not-named SNPs, anything over 10 will go over FTDNAs matching limit of combining all SNPs limit of 30.

                        I-Z2536 has 3 other brother sub-clades below, you will not match any of them

                        Go to www.familytreedna.com/public/y-dna-haplotree/A This phylogenetic tree is not just Big-Y, it includes other SNP tests

                        Enter i-F1997 into “go to branch name”

                        The first version of this phylogenetic tree had persons with no country entered listed, but the 2nd version deleted them. FTDNA shot themselves in the foot again. Now you have to go to the 3 vertical dots, which is confusing.

                        Click on the right 3 vertical dots for matches

                        You have 4 no country entered matches

                        At FTDNA the Sweden match is a brother sub-clade to you, so a different sub-clade

                        Next go to I project http://www.familytreedna.com/groups/...out/background

                        Its brick walled for non-members, if you are not a member please join. You will most likely find you matches there.

                        There is another way to find Big-Y matches by looking at your y-12, y-25, y-37 match list by clicking on the “Only show Big-Y”

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                        • #13
                          Thank you, I had done all of the tree examination you mention at both sites.

                          >> I recruited two distant cousins to test Big-Y and went from 2800 ybp to 175 ybp.

                          That is why I recruited a cousin this month, in the same hope.

                          I note here that YFull regularly informs me of any changes and updates to their tree, and that FTDNA most emphatically does not. As stated, my terminal at FTDNA has changed three times without any hints from FTDNA, I just happened to notice them because I look at my project so often. I find that very strange that I have to explicitly turn off 12-panel STR matches, but do not get any notifications of a fundamental change arising from the most expensive FTDNA test I have ever taken. (I was denied service from another, even more expensive and complete Y sequencer because I requested an estimated date of results, and my over $700 check was returned, that is another story in another thread.)

                          I am in all of the haplo projects for my I group, check them regularly, and am aware of and have contacted the specific admin on I1, from whom I have recorded some comments. My grouping at the I1 link you provide is with a grouping which does not include some of my matching YSTR members who have not done any test that would confirm equivalent A1892, even though I would predict that they would. Naturally I would have put them in the same group as I, but I understand that the lack of confirming SNP as opposed to predicted SNP is the dividing factor.

                          I am not happy that the access to projects of members from their kit pages is not available to admins any more during "impersonation." Lots of my members did not understand that even ADVANCED access is not truly FULL access, and so I cannot even look at my own personal project results from my own kit page when I am signed in as admin, which I am for about 90% of the time. This is extremely annoying when my members are asking me about their presence on these sites, since most of the time they cannot find themselves. I am a member of one of three haplogroups in my surname project, and strongly encouraged all members to join their respective haplo projects..

                          Ken Nortdvedt stated to me that he no longer accesses the page because he does not have the bandwidth, (Indeed, I get "Houston we have a problem" more than 50% of the time when I try to see my results there and am getting that right now.) It is Ken that has "named" my haplo as Anglo Saxon 889. I have his modality spreadsheet to look for my matches since FTDNA has made it just about impossible. About the only project where I have seen enough data to "bridge" the time-scales between SNP and STR testing is Maurice Gleeson's and he is clearly better-funded than I; we have only 3 men of our 50 members who have done Big Y and I just cannot fund these myself, even at sales prices.

                          Again, thanks for spending the time, basically duplicating my own efforts, but it is much appreciated. I still agree with the spirit of your original complaint, but I understand that by the lights of FTNDA's SNP interpretation, I have no matches. I have a few months to wait to see what happens with my cousin.
                          Last edited by clintonslayton76; 28 December 2018, 11:34 AM.

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                          • #14
                            I am FTDNA 206005 Clarke and my closest match is 392206 Deed. We have done Big Y. We are both at Y Full, and on The Big Tree. We are S-1491 > R-Y23824 on the YFull pages, and R-8493901-C-T at the Big Tree. At Y Full we have 11 common SNPs; the next closest to us at S1491 only have 2.

                            He and I correspond from time to time because we have a similar problem - parental G GFs were NPE. And we “think” our parental interests are only one County apart in the UK. However, the timeframe to MCRA is said at Y Full to be over 1700 years.

                            The Problem. What neither of us understand is how at FTDNA we don’t show up as a match to each other at any level at any page.

                            Can someone please explain how this can be so. Is there any test we can do to close the time gap.?

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                            • #15
                              Mudgeeclarke: The reason is quite simple. FTDNA needs to rewrite their Big-Y matching program. As an example, we had a new Big-Y results come in, NO Big-Y matches, when they do. One of these two had 23 Not-Named (Novel Variants) plus there are 6 SNPs that define the sub-clade, so 29 total. One less than FTDNA's limit of 30. So FTDNA must be using bogus or unreliable SNPs in their matching program. This problem goes all the way back to when FTDNA first started to offer the Big-Y test. I have emailed FTDNA multiple time about this problem.

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