A genome-wide CGI methylation analysis by Ricketts et al (9) showed that CGI hypermethylation of several genes (including SLC34A2 in 63%, OVOL1 in 40%, DLEC in 20%, TMPRSS2 in 26%, SST in 31% and BMP4 in 35% of RCC) is associated with transcriptional silencing, reactivation after demethylation in RCC cell lines and downregulation of expression in RCC. Here, BMP4 is linked to renal cell carcinoma.