TM6SF2 and hepatocellular carcinoma: Genetic factors, such as patatin-like phospholipase domain-containing protein 3 (PNPLA3) [20,21], transmembrane-6 superfamily member 2 (TM6SF2) [22], and programmed cell death-1 (PDCD1) encoding PD-1, are associated with NAFLD-related HCC initiation and progression [23].