Nonetheless, CpG island promoter methylation of the three Epi‐LumB proxy markers identified here (ZNF132, TTBK1 and KCNA3) are more consistently observed across all tumors of this subtype and thus more appropriate as proxies for identifying tumors of this subtype regardless of whether they represent true cancer driving events or not. The gene discussed is KCNA3; the disease is cancer.