DNA could be used for nefarious purposes. If eugenicists like the Nazis could have stolen Estonia's DNA records, they could have more efficiently committed genocide.

I can't find the story now, but there was one country which kept on file the religion of each citizen. Nazis gained control of the building with those records. Some rebels were successful in burning those files, saving many people's lives.

The historical record is full of key themes and tropes: our warlike behavior as whole, bias for tribalism, hatred and discrimination of minorities and society's propensity to rally behind those things.

To ignore the recent abuse of such data is ignoring the potential abuse DNA collection could enable.