An additional seven gene regions (EN1, PAX3, SIX3, SOX9, RFX1, SGK1 and NFE2L3) were chosen mostly on the basis of hypermethylation profiled by RRBS in breast cancer cells lines (and often other cancer cell lines) vs. the above-mentioned normal cell cultures or tissues [13]. The gene discussed is RFX1; the disease is breast cancer.