In CRC, epigenetic silencing of multiple TSGs has been reported frequently, including MLH1, p16INK4A, MGMT, VHL, APC, RASSF1A, HIC1, CHFR, ADAMTS18 and PCDH10 in various percentages of CRC tumours (Herman et al, 1998; Esteller et al, 2001; Kim et al, 2005; Ying et al, 2006; Jin et al, 2007 ). The gene discussed is CDKN2A; the disease is colorectal carcinoma.