RHOBTB2 and breast cancer: Potential targets in 8p23.3 and 8p22 have been discussed above while 8p21, although only affected by a single small deletion in this study, is the location of RHOBTB2, a candidate breast cancer gene based on the discovery of two somatic mutations [41], and the TRAIL receptors DR4 and DR5, which have been suggested as candidate cancer genes owing to their pro-apoptotic function [61].