Difference in transcriptional activity of the −402A allele. The CAT activities of constructs harboring one or two tandemly arranged 30 base pair fragments with either the wild-type (WT) site or the −402A site were compared in transfection studies using HepG2 cells. The constructs were tested in triplicate in four independent experiments. The CAT activities of the −402A-1x and −402A-2x constructs were expressed relative to the activities of the WT-1x and WT-2x constructs, respectively, the latter jointly indicated as WT. Bars indicate mean values and standard deviations. The statistical significance of differences was determined by Student’s pairedt-test.