Allergy-related polymorphisms influence glioma status and serum IgE levels

Previous studies have shown that glioma patients report allergies less frequently than controls, harbor lower atopy-associated IgE levels, and harbor different frequencies of polymorphisms in the IL13 and IL4 pathways than controls. We sought to confirm this latter result and extend the analysis to IgE levels. Glioma patients (n = 456) and controls (n = 541) were genotyped for genetic variants in IL4, IL4R, and IL13 and tested for total IgE levels (n = 248 controls and 289 cases). Among Whites, IL4 and IL4R polymorphisms and haplotypes were neither significantly associated with IgE levels in controls nor associated with glioma status. IL13 R110G and C-1112T were associated with increased IgE levels in controls (P < 0.001 and P = 0.04, respectively), and IL13 C-1112T was inversely associated with case-control status (P = 0.05, test for trend in dose model). An IL4R haplotype was borderline associated with increased risk in case-control analysis [odds ratio (OR), 1.5; 95% confidence interval (95% CI), 1.0-2.3]. In addition, a rare haplotype for IL4 was associated with decreased risk (OR, 0.23; 95% CI, 0.07-0.83), and a common haplotype in IL13 was associated with decreased risk (OR, 0.73; 95% CI, 0.53-1.00). Our data provide evidence for a role of IL13 polymorphisms on IgE levels and a role for IL4, IL4R, and IL13 haplotypes on case-control status. We did not find any evidence that the interleukin (IL) polymorphisms exerted their effect on glioma risk via their effects on IgE levels. Further exploration of immune susceptibility factors, including genetics, in glioma etiology is advisable.