Fig. 2. Effect of the NFKB1  polymorphism on the expression of the transcription factor NF-κB1 in the absence and presence of lipopolysaccharide. The LPS (225 µg/ml)–induced increase in NF-κB1 messenger RNA was markedly higher in volunteers with the deletion allele (ID/DD) compared with the II genotype. Data are the means ± SEM. DD = homozygous deletion; ID = heterozygous deletion; II = homozygous insertion; LPS = lipopolysaccharide.