To test this, transient transfection reporter gene assays were performed in HCMV-permissive HF cells using the luciferase reporter plasmid pA20(NF-κB)-Luc, which contains the A20 promoter region (from -95 to +9) with two NF-κB sites, and a synthetic pNFκB-Luc plasmid, which contains four copies of NF-κB sites (Figure 2A). This evidence concerns the gene NFKB1 and hydrops fetalis.