PNPLA3 and fatty liver disease: A recent genome-wide association study for Japanese patients with non-alcoholic fatty liver disease by Kawaguchi et al. revealed that the risk variant of PNPLA3 148 M is significantly associated with non-alcoholic steatohepatitis, but did not show significant differences in liver steatosis or fibrosis among the patients with non-alcoholic fatty liver disease (Kawaguchi et al.2012).