(2019) expanded this spectrum, revealing RARB/RARG fusions (e.g., TBL1XR1-RARB, CPSF6-RARG) and KMT2A rearrangements in morphologically similar cases, with RARA-negative patients showing inferior survival and higher relapse rates despite AML-style chemotherapy (13). The gene discussed is TBL1XR1; the disease is acute myeloid leukemia.