[Sabramerican]

This only affects the direct male line of ancestors

LOL. Guess you thought that out very clearly except for the fact that Judaism is only from the mother.

[Marduk]

"Guess you thought that out very clearly except for the fact that Judaism is only from the mother."

Judaism may officially go through the female line. But the Y-chromosome goes through the male line. Thus if you want to use the Jewish matrilineal definition of Judaism a proper study should study the mitochondrial DNA, not the Y-chromosome. The mitochondrial DNA is passed through the female line only.