not only genetics, in biochem i saw the same problem.
The biochem professor i noticed had his first two set of exams wore out there. I reported this to Dr.Y.
Dr.Y ofcourse very fast replied to my concern.
He said "Dont, worry he knows, and he will personally take care of everything''.

Cheaters, will always be cheaters. they will find a way. The only bad thing is that they screw up the curve for other people.