Yes, the 144,000 are from he 12 tribes, except the tribe of Dan, which is probably the tribe of which the anti Christ comes from. He is an Assyrian Jew
Many Jews will collude with the anti Christ to even destroy the race.
If you look at the "Jewish" Linage, it has a lot of other races throughout OT scriptures. So there has not been a "pure" Jewish race. A study of scripture in the NT has the Samaritans, which were both Jews and Gentile, but far more open to Christ, than the Jews. They will be gathered from all nations and will be mixed