Earliest Y-DNA Haplogroup In Japan? D2 or C1?

[Siginulfo]

Based on current evidence, which is the most likely pre-Jomon Y-DNA haplogroup in Japan? Which is the Jomon marker?

[Black Wolf]

I think that the Jomon people would mainly have been haplogroup D carriers.

[Prisoner Of Ice]

Ainu dna samples say D.