Associations between polymorphisms of the high-affinity immunoglobulin E receptor and late-onset airflow obstruction in older populations.
OBJECTIVE
To test the hypothesis that genetic polymorphisms in the beta subunit of the high-affinity immunoglobulin E (IgE) receptor are associated with late-onset airflow obstruction.


METHODS
Case-control candidate gene association study.


METHODS
Department of Medicine for the Elderly and Respiratory Medicine in three teaching hospitals in Leicester and Manchester, United Kingdom.


METHODS
Cases with late-onset airflow obstruction with age-, sex-, and geographically matched controls.


METHODS
Subjects were genotyped for two polymorphisms of the beta subunit of the high-affinity IgE receptor (RsaI intron 2 and RsaI exon 7). The association between the polymorphisms and phenotypes was examined using contingency tables and linear regression models.


RESULTS
Two hundred eighty-three cases and 144 controls were genotyped. RsaI exon 7 AA was associated with eczema (odds ratio (OR)=2.27, 95% confidence interval (CI)=1.17-4.38, P=.015). No other associations were found. Total serum IgE levels were significantly higher in cases than controls (adjusted OR for high/low IgE=2.56, 95% CI=1.53-4.28, P<.001).


CONCLUSIONS
Serum IgE levels, but not the high-affinity IgE receptor polymorphisms, were associated with late-onset airflow obstruction, suggesting that interaction between environmental and genetic factors controlling serum IgE levels and disease pathogenesis may differ between early- and late-onset airflow obstruction phenotypes.
Ruse
Charlotte E
CE
Institute for Lung Health, University of Leicester, Leicester, United Kingdom. charlotteruse@lycos.co.uk
Hill
Maureen C
MC
Burton
Paul R
PR
Connolly
Martin J
MJ
Wardlaw
Andrew J
AJ
Parker
Stuart G
SG
D000367:Age Factors; D000368:Aged; D001249:Asthma / Q000097:blood / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology; D016001:Confidence Intervals; D004485:Eczema / Q000235:genetics; D005260:Female; D005541:Forced Expiratory Volume; D005838:Genotype; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D016014:Linear Models; D008173:Lung Diseases, Obstructive / Q000097:blood / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology; D008297:Male; D010641:Phenotype; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology; D017455:Receptors, IgE / Q000235:genetics*; D012737:Sex Factors; D013147:Spirometry; D013997:Time Factors
D017455:Receptors, IgE; D007073:Immunoglobulin E