Even though α-fetoprotein (AFP) and protein induced by vitamin K absence-2 (PIVKA-II) are one of serologic markers widely used for diagnosing HCC patients, the elevated serum AFP is only observed in about 60% to 70% of HCC patients and, to a lesser extent (33–65%), in patients with smaller HCCs [92]. The gene discussed is AFP; the disease is hepatocellular carcinoma.