On the other hand, anti-HER1 monoclonal antibodies, which have been demonstrated good clinical results in cancer patients, are IgG1 antibodies (Dechant et al., 2008; Garrido et al., 2011; You and Chen, 2012) since IgG1 subclasses potently triggers effector mechanisms such as complement activation and antibody dependent cellular cytotoxicity (Garrido et al., 2011). The gene discussed is EGFR; the disease is cancer.