In the literature, it is reported that genes of antioxidant defense enzymes (ADE), such as glutamate cysteine ligase (GCLM), glutathione peroxidase (GPX1), catalase (CAT), myeloperoxidase (MPO), NADPH oxidase (CYBA, p22phox subunit), NAD(P)H: quinone oxidoreductase type 1 (NQO1), and microsomal epoxide hydrolase (EPHX1), are important determinants of genetic susceptibility to asthma in Russians [66]. This evidence concerns the gene CAT and asthma.