Pancreatic adenocarcinomas have some frequent genetic abnormalities in the mutational activation of the Kirsten rat sarcoma viral oncogene homolog (KRAS) oncogene; inactivation of tumor suppressor genes, including cyclin dependent kinase inhibitor 2A (CDKN2A), tumor protein P53 (TP53), mothers against decapentaplegic homolog 4 (SMAD4), and breast cancer type 2 susceptibility protein (BRCA2). The gene discussed is CDKN2A; the disease is pancreatic adenocarcinoma.