Suppose you are a childless mother and your ovaries are aching and you want a baby. But you don't want just any old baby. Andy you don't even want a genetically-engineered blue-eyed blonde baby. Suppose you are a young woman who adores Justin Bieber, and you want his baby.
You click on the DNA exchange, and buy his DNA. Your doctor modifies one of the mothers ovum, injects it with the celebrity DNA and implants in it her uterus. The celebrity pockets a cool $25,000 each time this happens.
Of course, the celebrities will have to watch out for fans pulling off a strand of their hair and sending it to a lab to isolate the DNA, and surreptitiously copy it.
It will be an interesting time. You can tell the age of a person by who he or she looks like. Where is this all going to lead? Myself, I think that it will lead the human race dumbing down. Imagine a whole generation of androgynous Justin Biebers walking around.