For a number of cancers it has been possible to identify particular genes that are methylated with high frequency, e.g., GSTP1 in prostate cancer [9,10], SHOX2 in lung cancer [11], SEPT9, NRDG4, RASSF1A, THBD, BCAT1 and IKZF1 in colorectal cancer (CRC) [12,13,14,15,16]. Here, IKZF1 is linked to cancer.