Correlations of IL-4R gene polymorphism and serum IgE levels with asthma predictive index

Abstract:

Objective To study the correlations of IL-4R gene polymorphism and serum IgE levels with asthma predictive index (API) in children. Methods One hundred and sixty-seven children with positive API, 187 children with negative API and 203 healthy children (control group) were enrolled. PCR and DNA sequencing were used to identify genotypes of the Arg551Gln locus in IL-4R gene. Serum IgE levels were measured using ELISA. Results There was no significant difference in the genotype frequencies of the Arg551Gln locus in IL-4R gene among the positive API, negative API and control groups. Serum IgE levels in the positive API group were significantly higher than in the negative API and control groups (P<0.01). In the positive API group, the children aged less than 2 years had significantly lower serum IgE levels than those aged over 2 years (P<0.01). Conclusions There is no correlation between the Arg551Gln polymorphism in IL-4R gene and API results. API positivity is correlated with elevated serum IgE levels. An older age (>2 years) may be a risk factor for increased serum IgE levels in children with positive API.