Although targeted mutation analyses of ROS1 or GOPC have not been performed in cancer samples, the Sanger Wellcome Trust COSMIC database (http://www.sanger.ac.uk/genetics/CGP/cosmic/) reported low frequencies of ROS1 sequence variations in ovarian (1/84), lung (8/131), breast (2/201), stomach (2/60), colorectal (1/133) and CNS tumours (3/477) [64]. Here, ROS1 is linked to cancer.