Chen et al. (2006a) reported that a combination of pre-S deletion mutations and BCP double mutations, rather than either alone, was associated with the development of HCC whilst other case–control studies reported that pre-S deletion is associated with the development of HCC but did not exclude the confounding effect of BCP double mutations (Choi et al., 2007; Lin et al., 2007; Gao et al., 2007). Here, OPN1SW is linked to hepatocellular carcinoma.