Race as a social and cultural construct and race as a genetic biological classification are very different, and it's probably not a good idea to hyper-focus on how exactly to classify everybody into groups.
Race is simply the acknowledgement of different phenotypes, which are determined genetically. I don't know why the left feels obligated to deny basic scientific facts when it comes to things like this; accepting the obvious reality of racial distinctions in no way entails racist beliefs.
Race is a categorization of phenotypes, so is the result of an interplay between genetics and historical conceptualizations.