Combining two validation studies with a total of 272 sporadic BC cases and 272 cancer-free female controls, we identified the blood-based hypomethylation in CD160, ISYNA1, and RAD51B as risk factors for BC in the Chinese population (CD160_CpG_3, CD160_cg20975414, ISYNA1_CpG_2, RAD51B_CpG_3 and RAD51B_CpG_4; odds ratios (ORs) per -10% methylation ranging from 1.08 to 1.67, p < 0.05 for all, by logistic regression adjusting for age and batch effects, Figure 2, Table 1). The gene discussed is ISYNA1; the disease is breast cancer.