This is a good (open) question and I can't answer it. Actually, no one can. Physicists are still investigating whether neutrinos are their own antiparticle (i.e. are neutrinos and antineutrinos the same object)? Hopefully, we will know more soon...

Concerning the studied dark matter models, in some of them the dark matter is its own antiparticle (anti dark matter equals dark matter) and in some other not. Both are very viable according to current data.