Allelic change from G (nonsusceptible allele) to A (susceptible allele) at the site of rs2794521 located in the promoter of CRP gene enhanced transcriptional activity of the promoter of CRP in HepG2 cells. A, schematic representation of the plasmid constructs. 915 bp fragment of CRP promoter (-858/+57) containing either the A or G allele (i.e. A and G promoter, respectively) was inserted in the pGL3-basic luciferase expression vector. Empty vector: pGL3-basic vector. B, HepG2 cells were contransfected with individual firefly luciferase (FLuc)expressing plasmid (A promoter, G promoter, empty vector) and pRL-TK as described in Materials and Methods. Cells were harvested after 24 hours, and relative luciferase activity (FLuc/Renilla luciferase) was determined. Fold luciferase activity of the variant A construct was 1- to 2-fold higher than that of the common G construct (P < 0.005). Data are present as fold-induction compared with promoter vector without insert. Bares are mean ± standard error of 3 different experiments, each performed in dulplicate.