I imagine the first person to do that would get a very low amount of money in return. Then in the future we will look back at that person like we do at the guy that bought a pizza for 10,000 BTC. Like, someone had to do it, and it wasn't worth much at the time, and if he didn't do it that way he probably would have done it some other way, but still the feeling remains that he could have gotten rich instead.

There are already hundreds of people sharing their whole genome sequence publicly.

http://www.personalgenomes.org/