MLLT10 is a transcriptional cofactor that plays crucial roles in chr10 regulation and gene expression. The protein functions as a cofactor for the histone lysine methyltransferase DOT1L, regulating histone H3 lysine-79 dimethylation (H3K79me2) and gene activation through binding to unmodified histone H3 1. MLLT10 demonstrates transactivation activity and binds to cruciform DNA structures, indicating its involvement in transcriptional regulation 1. In hematopoietic malignancies, MLLT10 fusion proteins are recurrent oncogenic drivers, with KMT2A::MLLT10 and PICALM::MLLT10 fusions associated with poor prognosis in pediatric acute myeloid leukemia, exhibiting 5-year event-free survival rates of only 18.6% 2. These fusion-positive leukemias demonstrate DNA hypermethylation signatures and activation of proliferation-related pathways 3. Beyond hematologic cancers, MLLT10 promotes tumor progression in colorectal cancer by enhancing migration, invasion, and metastasis through epithelial-mesenchymal transition mechanisms 4. Genome-wide association studies have identified MLLT10 as a risk locus for endometriosis, with potential roles in pain perception and inflammatory pathways 5. The protein's involvement in multiple cancer types and inflammatory conditions underscores its importance in disease pathogenesis.