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View Full Version : Charting of R-L226 (and other predictable haplogroups)



RobertCasey
07-10-2017, 02:01 AM
I am very fortunate that my Casey line descends from the second largest Irish haplogroup which is connected to King Brian Boru and his ancestors (who was the first king to unite / conquer the entire island of Ireland). Descending from a such a prolific line is very good for YDNA research. We just went over 550 testers at the 67 marker level or higher. Another very important factor that makes YDNA a good match for my Casey research - our YSTR signature is very isolated from the rest of haplogroup R (the signature does overlap with R1a but the genetic distance is over 20). So research of L226 will be leading edge due to being a prolific branch of mankind and being a genetically isolated (YSTR values) from everyone else.

These two issues lead to a very leading edge L226 project which has three very active and knowledgeable admins creating a very nurturing environment which now has 80 NGS tests, 80 L226 related SNP orders, several FGC NGS tests and a reasonable amount of YSEQ testing of private YSNPs. With a very genetically isolated YSTR signature and massive YSNP testing that recently revealed our 50th branch under L226, I have that I can now chart around 80 % of the 550 67 markers testers via signatures:

http://www.rcasey.net/DNA/R_L226/Haplotrees/L226_Home.pdf

However, we seemed to have hit a brick wall at 80 % coverage due to bias of testing of those more willing to invest in the future and those who want to get more immediate results (similar to atDNA testing being very popular). We are not well testing two ends of the bell curve statistically - based on the genetic distance from the L226 signature. Those that only have a genetic distance of only two or three (excluding the volatile CDY markers) in the last 1,500 years are testing some - but not as thoroughly as needed. Then we have those with very high genetic distance from the L226 who are not testing due to lack of good YSTR matches.

The L226 SNP pack increased coverage from 35 % to 70 % almost overnight and really doubled the number of testers who test at least 40 branches. We are now rarely revealing new branches from the 50 private and 50 branch equivalent YSNPs included the L226 SNP pack. Most of the time, newer Big Y tests are no longer revealing new branches as well.

Are others having similar experiences ? I think that the low genetic distance issue is probably bigger with L226 than most haplogroups but I know that M222 has the same issue. I see only four options to make the next big step:

1) Get the project to donate funds to YSNP test the extreme ends of the bell curve for genetic distance.

2) Wait until NGS testing has higher read lengths to cover all 111 markers that FTDNA tests and take the plunge to 400 YSTRs - I do not think 111 marker upgrades will help as much as targeted L226 SNP packs, more NGS tests or YSEQ testing.

3) Dip our toe into the Long Read YElite2.1 at $2,950 (2X coverage of Big Y) to reveal new major branches or wait for the price to come down. Around five percent of NGS tests are from FGC but these have been somewhat disappointing to date - no new major new branches but a couple of new more recent branches.

4) Vastly improve the L226 SNP to include many more private YSNPs to restart branch discovery and get interest in driving YSNP testing coverage again. Or really start encouraging YSEQ testing of the 500 known private YSNPs that now exist.