Mike,
I can only guess at the answer - but here goes
I think the difference you are describing is not really a breast difference, but a nipple difference.
Different nationalities, families seem to have slightly different nipple structures. So I would think it is genetic - like eye color. And that would mean there is nothing you can do to change it.
BUT some people do go to extreme meaures to change the shape of their bodies and people can chane their nipple from being not very prominent to prominent thru the use of what are commonly thought of as nipple torture devices.
Susan