This complex occurs in T-cell tumours and it is restricted to the immature CD4(- )CD8(-) thymocyte subset in asymptomatic transgenic mice.     ///    "In a transgenic model of tumorigenesis by Lmo2, T-cell acute leukaemias arise after an asymptomatic phase in which an accumulation of immature CD4(-) CD8(-) double negative thymocytes occurs. "