Nitric Oxide Synthase 2 Promoter Polymorphism Is a Risk Factor for Allergic Asthma in Children.

: In paediatric population, atopic asthma is associated with increased eosinophil counts in patients, that correlate with the airway inflammation measured by the concentration of nitric oxide in exhaled air (FeNO). As the FeNO level is a biomarker of atopic asthma, we assumed that polymorphisms in nitric synthases genes may represent a risk factor for asthma development. The purpose of this study was to analyse the association of genetic variants with childhood asthma in the Polish population. : In study we included 443 children-220 patients diagnosed with atopic asthma and 223 healthy control subjects. We have genotyped 4 single nucleotide polymorphisms (SNP) from 3 genes involved in the nitric oxide synthesis (, and ). All analyses were performed using polymerase chain reaction with restriction fragments length polymorphism (PCR-RFLP). We observed significant differences between cases and controls in SNP rs10459953 in gene, considering both genotypes ( = 0.001) and alleles ( = 0.0006). The other analyzed polymorphisms did not show association with disease. : According to our results, 5'UTR variant within isoform may have an impact of asthma susceptibility in the population of Polish children. Further functional studies are required to understand the role of iNOS polymorphism in translation and to consider it as a novel risk factor in childhood asthma. The next step would be to apply this knowledge to improve diagnosis and develop novel personalized asthma therapies.