First let me say that I am firmly in the rather let 1000 guilty folks go free rather than allow one innocent to be convicted camp.
Now, this is exactly how these things start. You have high-profile shows documenting how DNA evidence exonerated wrongfully convicted folks. Now, won't you kindly get in line to give your sample. It's only for future vindication should you ever find yourself wrongfully convicted. It's for the kids, don't ya know? It will come to pass, and we will allow it to happen, and that is the most disheartening thing about it.
EDITED to add that Imbro's right. FOr a movie that depicts just how this may be misused, check out GATTACA. And to further add that many have written books warning of many of the things that have come to pass, as well as those yet to come to pass, and still we do not heed the warnings.
"None are more hopelessly enslaved than those who falsely believe they are free." - Johann W. Von Goethe