Luciferase assay for GATA2 enhancer variant activity. Plasmids expressing firefly luciferase were cotransfected with a reference plasmid expressing Renilla luciferase into HL-60 cells. The A-to-T mutant constructs are indicated as mutant. (A) Schematic diagram of the plasmid constructs used to assay enhancer activity (refer to “Methods”). (B) Plasmid containing the SV40 promoter with the wt and mutant GATA2 enhancer element. Grand means from 3 separate trials are shown with standard deviations. The normalized luminescence is plotted as relative fluorescence units (RFU). The mutant enhancer signal was significantly higher than the wt enhancer: no DNA, 6.200 ± 3.654; vector, 33.85 ± 3.623; wt, 49.10 ± 4.109; and mutant, 88.66 ± 9.860. (C) Plasmid containing the GATA2 H1 promoter fragment with the wt and mutant GATA2 enhancer element. The normalized luminescence is plotted as relative fluorescence units (RFU). Grand means from 3 separate trials are shown with standard deviations: no DNA, 0; vector, 2.667 ± 0.5774; wt, 8.000 ± 3.606; and mutant, 11.67 ± 4.509.