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R-FCG71179, Discover, Block Tree and FTDNA matching
Most of my work is in the I haplogroup, but in trying to find transatlantic ancestors, we have promoted testing among men with a variant of our surname who are in Great Britain, Ireland or the Isles, or know that their male ancestor came from there within the last three centuries. So far, all are "R" haplo, and two have been good enough to do Big Y to meet the challenges posed by the "Atlantic Modal." One is completed and the other is in progress.
From the Discover tool at FTDNA, I interpret that among 37 men who are considered Tested Modern Descendants with SNP R-FGC71179, 0 (ZERO) of them show as Big Y matches for our sampler (we will call him Mr. Aberdeen, not his real name) and 0 (ZERO) are among his 37 to 111 YSTR matches. This begs a lot of questions: are any of these samples for men named like Aberdeen?; who are the men who are downstream: 29 men- R-BY45042, 2 men- R-FGC71171, 5 men-R-FT12728 and 1 yet unnamed lineage (Mr. Aberdeen?). These add up to 37, and that means that Aberdeen shares a massive proportion of Y chromosome with 36 men as seen on the Discover Time Tree for this SNP. We also look at the Block Tree at his kit page (reveals almost nothing helpful) and the Public Haplotree, which displays 20 for total with that SNP and three downstream SNPs.
My brain is in a fog as to how FTDNA filters out all of those other unknown men as not sharing enough yDNA to appear as matches at any level with Mr. Aberdeen. It seems improbable to me that all of those other men have opted out of public sharing and/or matching. We await the results of Mr. Aberdeen's cousin in the hopes of breaking what looks like a genetic logjam at an ancestor from at least 500 years BCE, but I still cannot wrap my head around the amount of shared yDNA Mr. Aberdeen has with other tested men, and that those other 36 downstream men are hidden from us as non-matches.
By contrast, I am among 8 tested descendants (acc to Discover) downstream of I-A11035, and: all 8 are on my Block Tree; all 8 are in my Y37 matches; 7 are in my Y67 matches; 6 of them appear in my Y111 matches, and the same 6 from Y111 are my Big Y matches, with 3 of them having a downstream from A11036 that is different from me and my two cousins. I would have expected a similar story with Mr. Aberdeen's matches. Someone check my thinking here.
From the Discover tool at FTDNA, I interpret that among 37 men who are considered Tested Modern Descendants with SNP R-FGC71179, 0 (ZERO) of them show as Big Y matches for our sampler (we will call him Mr. Aberdeen, not his real name) and 0 (ZERO) are among his 37 to 111 YSTR matches. This begs a lot of questions: are any of these samples for men named like Aberdeen?; who are the men who are downstream: 29 men- R-BY45042, 2 men- R-FGC71171, 5 men-R-FT12728 and 1 yet unnamed lineage (Mr. Aberdeen?). These add up to 37, and that means that Aberdeen shares a massive proportion of Y chromosome with 36 men as seen on the Discover Time Tree for this SNP. We also look at the Block Tree at his kit page (reveals almost nothing helpful) and the Public Haplotree, which displays 20 for total with that SNP and three downstream SNPs.
My brain is in a fog as to how FTDNA filters out all of those other unknown men as not sharing enough yDNA to appear as matches at any level with Mr. Aberdeen. It seems improbable to me that all of those other men have opted out of public sharing and/or matching. We await the results of Mr. Aberdeen's cousin in the hopes of breaking what looks like a genetic logjam at an ancestor from at least 500 years BCE, but I still cannot wrap my head around the amount of shared yDNA Mr. Aberdeen has with other tested men, and that those other 36 downstream men are hidden from us as non-matches.
By contrast, I am among 8 tested descendants (acc to Discover) downstream of I-A11035, and: all 8 are on my Block Tree; all 8 are in my Y37 matches; 7 are in my Y67 matches; 6 of them appear in my Y111 matches, and the same 6 from Y111 are my Big Y matches, with 3 of them having a downstream from A11036 that is different from me and my two cousins. I would have expected a similar story with Mr. Aberdeen's matches. Someone check my thinking here.
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