When BRAF V600E and non-synonymous changes in KRAS or NRAS were considered, methylation of the 5′UTR of C7orf49 and of the probe cg00172872 in the intergenic region on 12q21.33 remained significantly associated with trametinib in pancancer and breast cancer (5.24 × 10–13 ≤ pFDR ≤ 0.0023). The gene discussed is KRAS; the disease is breast cancer.