In conclusion, a total of nine methylated genes, including SFN, HOXA11, P16, RARβ, PCDHGB7, hMLH1, WNT5a, HOXD13, and RASSF1a, were methylated with significantly higher frequency in BC tissues than in matched normal breast tissues from 302 BC patients. This evidence concerns the gene RASSF1 and breast cancer.