Effect of preconception <i>SOD2</i> gene variants and air pollution on gestational length: evidence from a mother-baby cohort

To explore the relationship between air pollution, preconception <i>SOD2</i> gene variations, and gestational length. A study was conducted on 1,846 mother-baby pairs in Henan Province. Air pollutant was gathered from environmental monitoring stations. Peripheral blood was collected from pregnant women before pregnancy and genotyped to minimize the interference of prenatal air pollution on <i>SOD2</i> gene variations. Multivariable linear regression models were used to analyze the relationship between air pollution and gestational length, with an interaction term (SNP × air pollutant) included to explore the gene-environment interactions. After adjusting for covariates, it was found that exposure to carbon monoxide (CO), sulfur dioxide (SO₂), ozone (O₃), fine particulate matter (PM_2.5), and inhalable particulate matter (PM₁₀) was associated with decreased gestational length, while nitrogen dioxide (NO₂) exposure was associated with increased gestational length (<i>p</i> < 0.05). Furthermore, mothers carrying the A allele of <i>SOD2</i> rs4880 had an increment of 0.17 weeks in gestational length compared to those carrying the G allele (<i>p</i> < 0.05). Interactions on gestational length between <i>SOD2</i> gene polymorphisms (rs4880, rs5746136, and rs2758352) and exposure to CO, NO₂, SO₂, PM_2.5, and PM₁₀ were observed. These findings suggest that <i>SOD2</i> gene variations may influence the association between prenatal air pollution and gestational length.