A study on the CGI methylation level of GATA5 gene in RCC cell lines RCC-GS, 786-O, A498, ACHN, RCC-HS, as well as primary renal proximal tubular epithelial cells (RPTEC) using combined bisulphite restriction analysis (COBRA) revealed that the methylation level was 77 % in 786-O, 53 % in RCC-GS, 89 % in RCC-HS, 99 % in RCC-MF, 99 % in A498, 12 % in ACHN, and 2 % in RPTEC. This evidence concerns the gene GATA5 and renal cell carcinoma.