Female-biased association of NOS2-c.1823C>T (rs2297518) with co-susceptibility to metabolic syndrome and asthma

Abstract

The nitric oxide (NO) pathway contributes to the pathogeneses of metabolic syndrome (MetS) and asthma. NOS2 encodes inducible-NO synthase, which is an important enzyme of the pathway and its variations could affect the risk of asthma and MetS and thereby co-susceptibility to them. This study aimed to estimate the association of NOS2-c.1823C>T with risk of asthma, MetS, and asthma with MetS condition (ASMetS), and with asthma stages: intermittent, mild, moderate, and severe asthma. The study included asthmatics (n=555), MetS (n=334), and ASMetS cases (n=232) and 351 controls, which were genotyped by the PCR-RFLP method. The T allele was significantly associated with an increased risk of asthma and MetS in the sample population and females. CT genotype and CT+TT model were significantly associated with increased risk of ASMetS in females. A significant association between CT genotype and increased risk of ASMetS in the sample population and females was found in ASMetS vs. MetS. T allele significantly affects the risk of severe asthma in the sample population and females. The rs2297518 SNP of NOS2 contributes to the risk of MetS, asthma, and co-susceptibility to them, and this contribution may be stronger in females compared to males.