MMP2 and chromophobe renal cell carcinoma: Comparison of CpG methylation patterns in cRCC (VHL and sporadic wtVHL) and pRCC demonstrated that (at a 1% significance level using log-likelihood G-test) one gene (CDH1) was more methylated in the cRCC (29% vs 0%; p < 0.01) and 14 genes were more methylated in the papillary RCC (RASSF1, SERPINE1, HOXA11, HOXC6, JAK3, PDGFRB, MMP2, ITGB1, CREB1, MYOD1, GSTM2, TNFRSF10C, SMARCA3 and COL1A1 (see Additional file 2).