All ethnicities share this concern. For various reasons some believe a 'pure ethnicty' is desireable, and so try to control who intermarries with whom. Jews worry interfaith marriages will result in children not being raised Jewish, indians apparently worry interethnic marriage will result in children being half indian the first generation, quarter the next, and on n on.
Simple fact though is this is inevitible. Human race will eventually be so interbred the ethnicites as they exist now will be long gone. Sooner we're all some tannish shade the better. Though I'm sure we'll still find something to hate one another about. Stars on our bellies, or no stars on our bellies...