Our analysis confirmed the striking recapitulation of human disease features in the thymus-transplantation-based murine T-ALL model, including immunophenotype, genetic heterogeneity, frequency of somatic mutations, preponderance of Notch1 mutations, presence of mutations in known hematologic cancer genes and elevation of oncogenic transcription factor expression. The gene discussed is NOTCH1; the disease is hematopoietic and lymphoid cell neoplasm.