The caste system was put in place 1900 years ago but after the mixing of populations so caste system identification through dna isn't really possible.

And Jews were self identifying and dna isn't going to tell you if you are gay or not.

Ethnicity can be easier discovered through last name, visual clues rather then stolen hacker data.

The fears are similar to fears around your commodore 64
accidently logging into a war games scenario and destroying the world.

> Ethnicity can be easier discovered through last name

Most people in Russia who identify as Jewish and/or emigrated to Israel have non-Jewish last names. You really would never know if they didn't file the paperwork.

There are political parties in the world today speaking of remigration based on citizenship of family up to 3 or 4 generations. The data from 23andme would fit this purpose perfectly.

23andme data is not ancestry.com data. They lump you into groups from 100ad. Hard to match to country origins when groups are broadly called northwestern european which combines Ireland, UK, Sweden, France, Germany, Sweden, etc into one group.

Wouldn't they use the citizenship data they have from the last 100 years? If they used 23andme data wouldn't they have floods of people from US, Canada, Australia, who could claim a new citizenship?