Ok, folks, so I'm new here.
I have recently badgered about half a dozen folks from my surname of interst to 'go' for Y-DNA testing.
Some of the results are back and posted. Two of the posted entries have 4 mis-matches in the first 12 markers (one opted or a 12 marker test, the other told me his was a 37 marker but only 24 markers are posted at present).
Am I safe to conclude that means they are definitely not related?
Another participant (who also ordered a 12 marker, on my suggestion) told me he didn't really understand the results he got back but was told he was related to one of the two whose results are posted.
Until his results get posted, am I safe to conclude that probably means a perfet match in the 12 markers between himself and this other person?
I've seen somewhere that one mismatch in 21 (or 24) markers means the MRCA was 8.3 generations back. I also read that two mismatches means the MRCA was 20.5 generations back, and three mis-matches pushes it to 33.2 generations back. And yes, I've seen the statistical accuracy numbers for each case.
How many generations back to the MRCA for 4 mismatches? For 5? For 6 or more?
What if some of these mismatches are _not_ in the fast moving markers? How does that impact the intrepretation?
Do I need a 4 yr course in this stuff? I sure hope not because I'm not at all sure that, at my advanced age, I could live long enough to finish it...