We have identified a minor BCR within the human MLL gene that is recurrently associated in acute leukemia patients with MLL-USP2 fusion alleles as well as MLL fusion partnerships with USP8,AF4, and AF9. However, with 17 cases out of ~2500 analyzed patients the incidence is less than 1% while still ranking fourteenth of our updated fusion gene list (see Table 1 of reference1).The discovery of a second, minor BCR extends ourknowledge of the MLL-recombinome and MLL-r oncogenesis.
Moreover, thesefindings will enable many labs tomake changes in their diagnostic set-up for MLL-MRD diagnostics to ensure the best medical treatment for a group of patients that is still very hard to cure.