User blog comment:AokijiSencho/Theory on Chopper and Luffy/@comment-4469678-20140709145908

I have this theory that the WG, after executing Roger, kept his body to study the disease and Vegapunk managed/will manage to weaponise the disease. This will be given to Luffy and his is where Chopper will achieve his dream, being able to cure diseases which were thought incurable.

Will definitely happen with a lesser author, but Oda will either circumvent it in his own ridiculous way or provide a new twist to it.