As a HAPI gene, MYC has most of its enhancer activity contributed in cis. Interestingly, CDX2, a colorectal cancer lineage-survival oncogene49,50 from chromosome 13, is identified as a trans-enhancer hijacking HAPI gene (Fig. 4B), with over 95% of enhancer activity in trans. The gene discussed is CDX2; the disease is colorectal cancer.