Gene by Environment Interaction: The −159C/T Polymorphism in the Promoter Region of the CD14 Gene Modifies the Effect of Alcohol Consumption on Serum IgE Levels

Abstract

Serum IgE is increased in heavy drinkers. Endotoxin mediates most of the immunological alterations associated with heavy drinking. The -159C/T polymorphism in the promoter region of the gene encoding CD14 (an endotoxin receptor) is associated with serum IgE levels in different populations. To investigate the possible interaction between alcohol intake and the -159C/T polymorphism in the promoter region of the CD14 gene for serum IgE levels. A total of 415 individuals (51.6% males, median age 50 years, range 18-92 years) were studied. A total of 140 individuals were alcohol abstainers, 112 were moderate drinkers (1-280 g/week), and 163 were heavy drinkers (>280 g/week). Main determinations included the CD14/-159C/T genotype, a panel of skin prick tests, total serum IgE, and specific serum IgE against common aeroallergens (Phadiatop test). Heavy drinking was associated with increased total serum IgE values and with positive specific serum IgE to common aeroallergens, but the association was stronger in carriers of the CD14/-159C allele (either CC homozygotes or CT heterozygotes) than in CD14/-159TT homozygotes. Both additive and multiplicative interactions between heavy drinking and the CD14/-159C allele for total and specific serum IgE values was still present after adjusting for potential confounders. Neither alcohol consumption nor the CD14/-159 genotype was associated with skin prick test positivity. The CD14/-159C/T polymorphism modifies the effect of alcohol consumption on serum IgE levels.