I wonder what the degree of relatedness (assuming inbreeding) these descendants actually have with Genghis Khan. We know that family trees break down into direct acyclic graphs over the longer term.

Note that the title assumes just patrilinear descent, so any man that may have had only daughters will not pass on the Y chromosome, though he will still have a non-patrilinear lineage (carried by both sons and daughters).

BTW, what are the main structural differences between strictly male and strictly female lineages?