This is an interesting topic.
Ive got one that is a biter and the other is not. The biter has drawn blood on me a few times. Im not rushing to kill her. When I clean out the cage I grab her by the tail. Other than that when I add food I use a shield on the biter so I can finish doing what I need.
But really I cant see this a being a gentic trait passed on. Alot of it is imo lack of human socialization. If you start early handling the babies to show that your not a threat. I dont see a reason why the should bite. None of my babies from her have tryed to bite me so far... the worse thing they think is my hand is a jungle gym.
I have fed the daddy off, because of inbreeding with his sis's. So I kept the other male to outbreed. Neither did the daddy or this new male I have was/is a biter.
Could it be gentic? I highly doubt it but no way to prove it. But what it boils down to is lack of human socialization as a baby. Thats my 2 cent.