Recently, the single-nucleotide polymorphism (SNP) of rs738409 patatin-like phospholipase domain-containing protein 3 (PNPLA3) has been identified for its significant associations with liver steatosis and fibrosis in patients with fatty liver disease and alcoholic liver disease (Romeo et al.2008; Valenti et al.2010). The gene discussed is PNPLA3; the disease is fatty liver disease.