I'm Caucasian, as you can clearly see in my avatar, and I would say that the ENFP typing is very widespread. As far as typing being genetic, that question spans back to the basic nature vs. nurture argument in sociology and psychology. The nature argument suggests that every aspect of our psychological being (temperament, intelligence, personality, etc.) is hardwired into us at birth with very little room for variation. Nurture suggests that we are conceived with a clean slate and our enviournment determines a vast majority of what we are like as we grow. It all depends on which professional you ask.
Through research and conclusions based on said research, I believe that we are wired with certain aspects of ourselves, such as our food preferences and general temperament, but these can be changed through enviournmental factors. For example, a child could be born to have a dislike for cabbage, but is raised in a family where cabbage is a main source of food. As time goes on, the child will grow to tolerate or even like cabbage as an adult. The same is possible for personality types. Someone could be born an ENFP, but with an extremely strict family and years of redirection, the child could grow to become an INTJ or something of the sort. The opposite may be true for INTJs that are raised in a family that encourages expression of feeling and are good at picking up on body language/expressions. This may result in an ENTP, or even an ENFP (though an ENFP could be a stretch there). Granted, these are just my conclusions, and they do not have much scientific backing as far as personal experiments go.