The breakdown of the mucosal barrier then permits bacterial translocation (Hackam et al., 2013; Leaphart et al., 2007; Neal et al., 2013a), which activates TLR4 on the intestinal mesenteric endothelium (Yazji et al., 2013), resulting in loss of endothelial nitric oxide synthase, intestinal hypoperfusion and intestinal ischemia leading to NEC. The gene discussed is TLR4; the disease is necrotizing enterocolitis.