High serum IL-6 concentrations in endometriosis patients are probably related to the reduction in conserved helix-loop-helix ubiquitous kinase (CHUK) protein as well as NF-κB inhibitor alpha (NFKBIA) mRNA and the p-NFKBIA/NFKBIA protein ratio. The gene discussed is NFKBIA; the disease is endometriosis.