Synergistic Effect of Genetic and Environmental Factors in Childhood Asthma

Asthma is a result of a complex interaction between host genetic factors and environmental factors such as viral respiratory infections and exposure to tobacco smoke. Genome-wide association studies have identified strong associations between single nucleotide polymorphisms (SNPs) at the 17q21 locus and susceptibility to childhood asthma. Most childhood asthma exacerbations are caused by viral infections, especially human rhinovirus (HRV), but it is unclear why some children are more prone to HRV-induced wheezing and why only some children who wheeze with viral respiratory infections go on to develop true asthma.

Researchers examined the risk for asthma associated with 17q21 genotypes and HRV or respiratory syncytial virus (RSV) wheezing ill…