Published online: February 3, 2017
Asthma is a multifactorial disease, resulting from complex interactions between an individual’s genes (or genetic predisposition) and environmental exposures. Specific genetic variants may confer risk (or worsen disease) only in the presence of certain environmental exposures, a phenomenon called gene-by-environment (GxE) interaction.
In the study published in this issue of The Journal of Allergy and Clinical Immunology (JACI), Forno and colleagues aimed to identify genetic variants that modify the effects of dust mite exposure on worsening lung function in children with asthma. Using data from a study of Puerto Rican asthmatic children, they looked at over 1.8 million genetic variants (called SNPs), and evaluated whether their association with lung function differed depending on the level of dust mite to which each child was exposed at home. They then validated their main findings in an independent population, using data from the Childhood Asthma Management Program (CAMP).
The researchers found several SNPs in Puerto Rican children that interacted with dust mite levels to affect FEV1, a measure of lung function. Of these SNPs, the association with one –rs117902240– replicated in CAMP non-Hispanic white and Hispanic children. This SNP was associated with higher FEV1 (better lung function) in children exposed to low levels of dust mite at home, but it was associated with lower FEV1 among children exposed to high levels of dust mite. They also found that the SNP might have regulatory functions in pathways related to immunity and asthma.
In summary, this is the first genome-wide interaction study of dust mite exposure on lung function in children with asthma. Future studies will be needed to determine whether personalized interventions for these children (for example, reducing dust mite exposure) will have a greater impact on their lung function.
The Journal of Allergy and Clinical Immunology (JACI) is an official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.