Psychosocial Stressors, DNA Methylation in Airway Epithelium, and Asthma in Children

Rationale: Exposure to violence (ETV) affects stress responses and may influence asthma pathogenesis. We hypothesized that ETV or stress is linked to asthma through altered DNA methylation in airway epithelium. Methods: Cross-sectional study in 487 Puerto Ricans (aged 9-20 years) with (n= 237) and without (n= 250) asthma (EVA-PR). We measured DNA methylation in nasal epithelium using the HumanMethylation450 BeadChip and assessed genome-wide (GW) genotypes using the HumanOmni2. 5 BeadChip platform (Illumina, San Diego, CA). We assessed ETV and chronic stress in the child and her/his mother. As in prior work, the child’s ETV scale was analyzed as continuous, the child’s lifetime exposure to gun violence (ETGV) was analyzed as binary (having heard no gunshots vs.≥ 1 gunshot), and perceived child stress (assessed by the checklist of children’s distress symptoms, CCDS) and maternal …