Polymorphisms in the 5 ' region of the CD14 gene are associated with eczema in young children

Harvard University, Cambridge, Massachusetts, United States
Journal of Allergy and Clinical Immunology (Impact Factor: 11.25). 06/2005; 115(5):1056-62. DOI: 10.1016/j.jaci.2005.02.006
Source: PubMed

ABSTRACT Variants in the CD14 gene (CD14) are hypothesized to be associated with atopic disorders. However, most studies have only investigated one polymorphism in this gene.
We sought to study the association of 5 single nucleotide polymorphisms (SNPs) in the 5' flanking region of CD14 with eczema and serum IgE levels in young children.
We genotyped 5 SNPs in an approximately 6.5-kb region in the 5' region of CD14 in 344 2-year-old white children from 2 birth cohorts in the northeastern United States. We examined the relation of both single SNPs and haplotypes in CD14 with the atopic outcomes.
Two SNPs were significantly associated with eczema. In dominant models adjusted for potential confounders, SNP rs2569193 was associated with significantly decreased risk for eczema (odds ratio [OR] for CT/TT vs CC, 0.5; 95% CI, 0.3-0.8), whereas SNP rs2569190 (also reported as the C-159T) was associated with significantly increased risk for eczema (OR for CT/TT vs CC, 2.3; 95% CI, 1.4-3.8). The CT/TT genotypes of SNP rs2569190 also had higher geometric means of serum IgE than the CC genotype (24.6 vs 15 IU/mL, P = .025). Haplotype analyses provided results similar to those of the single SNP analyses.
Our results contradict previous reports that have found a protective effect of the T allele of SNP rs2569190 (C-159T) against atopic disorders. Nevertheless, these results confirm the importance of polymorphisms in CD14 in the development of atopy, and future studies of this gene region will need to account for linkage disequilibrium and environmental exposures unique to the study population.

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    • "Wang et al. (21) 2005 Chinese The T allele was associated with elevated IgE when the T allele was part of a haplotype containing a D5S2011 E allele. Litonjua et al. (14) 2005 Caucasian in America Infants with CC/CT genotypes had significantly increase risk for eczema and elevated total IgE. Kedda et al. (41) 2005 Caucasian in Australia There was a weak association (P = 0.084) with the T allele that was associated with atopy. "
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