Lmo2 is expressed within immature CD4/CD8 double-negative thymocytes and aberrant Lmo2 expression in committed and immature T-cells in the thymus led to self-renewal, an accumulation of early precursors, and transformation of T-cell precursors to T-ALL (Figure 2) [25]. The gene discussed is LMO2; the disease is acute lymphoblastic leukemia.