I don't read serious medical journals, I'm afraid. I've heard it on discussions about the subject. I realize that anecdotal stories are not the same as scientifically proven data, but often it is the stories which lead to studies that prove the claims. I have no real opinion on the subject, but it's not at all the first time I've heard it.
Methinks it's an urban legend. I scan the headlines from medical news almost daily, and have never heard a whiff of any such thing. Sounds like it's a fictional extrapolation from factual information and/or serious hypotheses about subtle changes that a transplanted organ might have on a recipient, such as beginning to produce antibodies that the donor had been producing, but the recipient hadn't been.