Currently, it is speculated that age-related loss-of-function mutations in the TET-2 and DNMT3A genes, which occur at an early-stage of hematopoietic development, constitute the initial events that promote the tumor (first hit), since they are found in clonal TFH-cells, in B-cells and in CD34+ myeloid precursors. This evidence concerns the gene DNMT3A and neoplasm.