RNF8 and thymoma: Interestingly, even though Rnf8 and Rnf168 have been proposed to function in the same DNA damage signaling pathway, the tumor spectrum of Rnf8−/−p53−/− mice was different from what was observed in Rnf168−/−p53−/− mice which develop primarily B-cell lymphomas, followed by thymomas and sarcomas [28].