In order to test this hypothesis we analysed in this study polymorphisms in the RMI1, TOP3A and BLM, and their association with cancer risk in available case-control materials, namely AML/MDSs (acute myeloid leukemia and myelodysplastic syndromes), malignant melanoma, and bladder and breast cancer. The gene discussed is BLM; the disease is acute myeloid leukemia.