Asthma Risk Linked to Gene Variants and Auto Pollution
Incidence increases when predisposed children live near major roads
WEDNESDAY, Aug. 22 (HealthDay News) -- Proximity to major roads is associated with substantially greater risk of asthma in children who are genetically susceptible to the disease, according to a report published online Aug. 21 in the journal Thorax.
Frank D. Gilliland, M.D., Ph.D., of the University of Southern California Keck School of Medicine in Los Angeles, and colleagues analyzed data on 3,124 children (aged 10, 13 and 16) drawn from the Children's Health Study. Of these, 476 (15.5 percent) were diagnosed with asthma.
The investigators found that children with high activity microsomal epoxide hydrolase (EPHX1) phenotypes together with variations in glutathione S-transferase P1 genes had a lifetime risk of asthma four times greater than children with lower or intermediate activity EPHX1 phenotypes. Children with both variants who lived within 75 meters of a major road were found to be up to 8.91 times more likely to develop lifetime asthma.
"Based on these findings, we hypothesize that specific polyaromatic hydrocarbon mediated generation of o-quinones and reactive oxygen species could be a pathway for the pathogenesis of asthma in childhood," the authors conclude.