We have an unknown 2xgreat grandfather in our family tree. We tested my cousin, since he carries the paternal line from that unknown ancestor and we need every clue possible.

I entered my cousin's 111 marker results from FTDNA into the Nevgen calculator. It returned, with 100% probability, this: R1b=>U106=>Z381=>Z301=>L48=>BY12508.

Two questions come to mind. Is this path to be trusted, especially given 100% probability? And, is it at 100 % because R1b is so extensively sampled that the relationships between STRs and SNPs are well-established?