Figure 4

Methylation analyses of ETV6 and CDKN1B . a1/a2: Schematic view of the ETV6/CDKN1B-CpG islands: each vertical bar represents a single CpG site. Arrows indicate the start of the non-coding exon 1 and the start codon. The positions of the PCR product and the product used for pyrosequencing are indicated below as horizontal bars. b1/b2: A representative pyrogram determining the nucleotide sequence within the CpG island of ETV6/CDKN1B. The sequence in the upper part of the pyrogram contains a Y at positions under investigation, the sequence below indicates the injected bases during pyrosequencing. Highlighted areas in the pyrogram indicate variable CpG positions (light gray). The methylation level of each CpG site is indicated in blue boxes on top of the pyrogram. c1/c2: Mean methylation levels of the 23 CpG sites in the 5′UTR of ETV6 and the 22 CpG sites in the 5′UTR of CDKN1B of all patients analyzed are shown as a percentage. The standard deviation was determined using the Kruskal-Wallis test.