Race is genetic in the same way ROYGBIV is about wavelengths: wavelengths cause the different colours, but there's no real reason to say "this is red, but this

Race is genetic in the same way ROYGBIV is about wavelengths: wavelengths cause the different colours, but there's no real reason to say "this is red, but this is orange" - the wavelengths don't care how we categorise these things! In the same way, genetics certainly determines a lot about our appearances, but definitions of "black", "white", "Asian", "hispanic", etc are just categories that we humans have defined on top of a much more complex underlying structure.