Baseline lung function, quantified as forced expiratory volume in the first second of exhalation (FEV), is a standard diagnostic criterion used by clinicians to identify and classify lung diseases. Using whole genome sequencing data from the National Heart, Lung, and Blood Institute TOPMed project, we identified a novel genetic association with FEV on chromosome 12 in 867 African American children with asthma (p = 1.26 × 10, β = 0.302). Conditional analysis within 1 Mb of the tag signal (rs73429450) yielded one major and two other weaker independent signals within this peak. We explored statistical and functional evidence for all variants in linkage disequilibrium with the three independent signals and yielded 9 variants as the most likely candidates responsible for the association with FEV Hi-C data and eQTL analysis demonstrated that these variants physically interacted with and their minor alleles were associated with increased expression of gene in nasal epithelial cells. Gene-by-air-pollution interaction analysis found that the candidate variant rs58475486 interacted with past-year SO exposure (p = 0.003, β = 0.32). This study identified a novel protective genetic association with FEV, possibly mediated through , in African American children with asthma. This is the first study that identified genetic association between lung function and , which has established role in orchestrating allergic inflammation in asthma.