1. People are inherently biased if they identify with any social group, tradition or practice. But it also includes education, upbringing and peer pressure.
2. Science operates on the basis of algorythms and social patterns that don't always take nuances and exceptions into account.
3. The majority's claim to power should depend on their treatment of minorities. Since it's rarely the case, society becomes an experiment for right-wing ideologues with concepts like Aryan families in Nazi Germany. In my country, you're good as long as you're not in a mixed marriage.
4. When that happens, social science turns into totalitarian propaganda, which starts with stereotypes and ends up with ethnic cleansing.