The lack of NOX2 elevation in the group of NAS subjects is also in line with evidence demonstrating that hypoxia leads to the production of nitric oxide and superoxide, essentially through the increased expression and activation of cytoplasmic,45 as well as mitochondrial,46 nitric oxide synthases and through the generation of superoxide anions, essentially by mitochondria.47 However, a minor impact of asphyxia on NADPH oxidase expression and activity cannot be totally excluded. The gene discussed is FMO5; the disease is neonatal abstinence syndrome.