Isn't this exactly the premise of the movie Gattaca? Great movie, BTW.
IMO Gattaca makes a great case for genetic testing. An idiot with a major heart condition bluffs his way onto a space mission where he's likely to die and endanger the rest of the crew. If the testing had been a bit more thorough (say, if the doctor in charge of testing had done his job) then the mission wouldn't have been endangered. It's strange to see everyone hold up this movie as an argument against this sort of…
The character is also clearly not an idiot.