Biologically in the sense that we have affinities towards our own names or initials which studies have shown. Just a consequence of how our brains organize information.

Instead of someone drilling into your head that your initials = good, and others = bad via your environment, it happens through natural processes.

Most biases are just pattern matching which is necessary for efficient memory references and power quick on-the-spot judgements/decisions we need to make. People make too much of a big deal out of stereotypes like it's evil to hold them even though it's a basic function of the brain. It's entirely possible without constant vigilance to make misjudgements based on that but it will still happen to everyone, even the most socially aware people.