We studied the DNA methylation status of specific loci, including SFRP1, SFRP2, SFRP5, DKK2, DKK3, mir34b/c, RASSF1A, IGFBP7, CDKN2A, and MLH1. In this way, we determined their involvement in CRC development in isolated normal and cancerous crypts. The gene discussed is RASSF1; the disease is colorectal carcinoma.