For example, there are 342 genes whose abnormal methylation might relate to lung cancer and the top 11 genes having at least 20 papers include CDKN2A (cyclin-dependent kinase inhibitor 2A), RASSF1 (Ras association domain family 1), TP53, MGMT, DAPK1 (death-associated protein kinase 1), RARB (retinoic acid receptor, beta), HRAS (v-Ha-ras Harvey rat sarcoma viral oncogene homolog), RB1 (retinoblastoma 1), APC, FHIT (fragile histidine triad gene) and GSTP1. Here, HRAS is linked to lung carcinoma.