Inactivation of tumor suppressor genes, including p53 and pRb, and activation of proto-oncogenes including Ras, c-myc and c-fos, telomere shortening, single nucleotide variants, small deletions and mutations in TERT (telomerase reverse transcriptase), APC (adenomatous polyposis coli), and CTNNB1 (catenin beta 1) genes are among the most common types of molecular disorders in HCC. The gene discussed is TERT; the disease is hepatocellular carcinoma.