A population-based survey found that the level of IL-6 in cerebrospinal fluid after perinatal asphyxia correlated with the severity of neonatal hypoxic-ischemic encephalopathy (HIE), brain injury and neurological outcome, suggesting a role for IL-6 in neonatal hypoxic-ischemic brain injury (Martin-Ancel et al., 1997). This evidence concerns the gene IL6 and perinatal asphyxia.