Stop it. That's a lame ass excuse.
Nobody is born racist.
It's a product of society.
Humans are social animals that balkanize towards racial, linguistic, cultural and religious similarities. Fifty plus years of mass immigration and multiculturalism should be enough to prove this point. We are creatures who are not made to live in a mass, global society productively and happily, it is beyond our biological scale. Most multicultural societies are wealthy, this is why you still see some level of social trust, but, let their be a food shortage, or a water shortage and watch how quickly people balkanize to fight for those resources collectively.