A ROC curve showed that when the sensitivitywas 86.67% (RANBP3), 82.35% (LCP2) and88.24% (GRAP2), the specificity of breast cancerdiagnosis was 93.3%; the sensitivity of identifyingbreast cancer patients by the comprehensive methylationlevel of the three genes was 94.1%, with aspecificity of 93.3%. The gene discussed is RANBP3; the disease is cancer.