Researchers Identify Alleles Associated With Asthma
Find several links of genome-wide significance, including one specific to childhood-onset disease
WEDNESDAY, Sept. 22 (HealthDay News) -- Researchers have identified a handful of common alleles that are related to the risk of developing asthma, and their findings have been published in the Sept. 23 issue of the New England Journal of Medicine.
In a genome-wide association study, Miriam F. Moffatt, Ph.D., of Imperial College in London, and colleagues genotyped 10,365 individuals with physician-diagnosed asthma and 16,110 unaffected individuals, all of whom were matched for ancestry.
The researchers found links of genome-wide significance between asthma and single-nucleotide polymorphisms, including rs3771166 on chromosome 2, implicating IL1RL1/IL18R1; rs9273349 on chromosome 6, implicating HLA-DQ; rs1342326 on chromosome 9, flanking IL33; rs744910 on chromosome 15 in SMAD3; and rs2284033 on chromosome 22 in IL2RB. The researchers also found that the association with the ORMDL3/GSDMB locus on chromosome 17q21 was specific to childhood-onset asthma. Loci strongly related to IgE levels were not associated with asthma, and only HLA-DR showed a significant genome-wide association with total serum IgE concentration.
"The relative risks observed with our markers will not be useful as predictors of disease in individual patients, no doubt because of variable environmental effects. These loci nevertheless contribute substantially to the asthma burden in the general population," the authors write. "Further studies are needed to identify the specific genetic variants that contribute to disease and to establish their biologic function."