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Atopy Phenotypes (atopy + phenotype)
Selected AbstractsORIGINAL ARTICLE: Chronic urticaria is associated with a differential helminth,arthropod-related atopy phenotypeTHE JOURNAL OF DERMATOLOGY, Issue 9 2010Alvaro DASCHNER Abstract The relationship between atopic sensitization and chronic urticaria is still controversial. In this study, we aimed to compare the prevalence of aeroallergen sensitization in chronic urticaria patients with (CU/As+) and without (CU/As,) sensitization against Anisakis simplex. Forty-nine CU/As+ and 80 CU/As, patients were studied and skin prick tests (SPT) were performed against aeroallergens. We assessed sensitization in a subgroup of patients with allergic rhinoconjunctivitis and/or bronchial asthma (RCBA) and compared the prevalence with a control group of 522 non-urticaria patients with RCBA. Forty-five percent of CU/As, and 60.4% of CU/As+ patients displayed positive SPT to at least one aeroallergen. CU/As+ patients had a higher prevalence of sensitization against pollen, mould or dander (PMD) (52.2% vs 29.1%, P < 0.01), whereas the prevalence of house dust mite (HDM) sensitization was not statistically different (26.3% in CU/As, and 36.7% in CU/As+). However, in chronic urticaria patients with RCBA, 53.8% of CU/As, and 57.9% of CU/As+ patients differed in the prevalence of HDM sensitization compared to the control group (33.5%, P = 0.03), whereas no difference could be stated for PMD sensitization. Compared to RCBA patients, both CU/As+ and CU/As, patients have a higher clinically relevant sensitization rate against HDM, thus displaying a differential atopy phenotype. [source] Common polymorphisms and alternative splicing in the ILT3 gene are not associated with atopyINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 3 2000A. Heinzmann Recently, a linkage of the chromosomal region 19q13.4 with bronchial asthma has been demonstrated. This region harbours the so-called leucocyte receptor cluster with the gene for immunoglobulin-like-transcript 3 (ILT3) as a member. ILT3 represents an inhibitory receptor bearing three immunoreceptor tyrosine inhibitory motifs (ITIM). The protein mediates downregulation of cell activation through recruitment of different SH2-containing protein tyrosine phosphatases. With regard to the negative immunoregulatory function particularly on B-cells, ILT3 represents a candidate gene for atopy and asthma. The aim of this study was to screen for common polymorphisms in the gene coding for ILT3 and to test for association with the atopic phenotype. Using single-stranded conformal polymorphism-analysis and direct genomic sequencing seven polymorphisms, three mutations, a common deletion of 7 bp in the third intron and evidence for further alternative splicing of the ILT3 gene were found. Although no association was found with atopy phenotypes, it might prove useful to test for association with bronchial asthma. [source] Polymorphisms in IL13 pathway genes in asthma and chronic obstructive pulmonary diseaseALLERGY, Issue 4 2010B. Beghé To cite this article: Beghé B, Hall IP, Parker SG, Moffatt MF, Wardlaw A, Connolly MJ, Fabbri LM, Ruse C, Sayers I. Polymorphisms in IL13 pathway genes in asthma and chronic obstructive pulmonary disease. Allergy 2010; 65: 474,481. Abstract Background:, Asthma and chronic obstructive pulmonary disease (COPD) are chronic respiratory diseases involving an interaction between genetic and environmental factors. Interleukin-13 (IL13) has been suggested to have a role in both asthma and COPD. We investigated whether single nucleotide polymorphisms (SNPs) in the IL13 pathway may contribute to the susceptibility and severity of asthma and COPD in adults. Methods:, Twelve SNPs in IL13 pathway genes ,IL4, IL13, IL4RA, IL13RA1, IL13RA2 and STAT6, were genotyped in subjects with asthma (n = 299) and in subjects with COPD or healthy smokers (n = 992). Genetic association was evaluated using genotype and allele models for asthma severity, atopy phenotypes and COPD susceptibility. Linear regression was used to determine the effects of polymorphism on baseline lung function (FEV1, FEV1/FVC). Results:, In asthmatics, three IL13 SNPs , rs1881457(,1512), rs1800925(,1111) and rs20541(R130Q) , were associated with atopy risk. One SNP in IL4RA1 [rs1805010(I75V)] was associated with asthma severity, and several IL13 SNPs showed borderline significance. IL13 SNPs rs1881457(,1512) and rs1800925(,1111) were associated with better FEV1 and FEV1/FVC in asthmatics. IL13 SNPs rs2066960(intron 1), rs20541(R130Q) and rs1295685(exon 4) were associated with COPD risk and lower baseline lung function in the recessive model. In females, but not in males, rs2250747 of the IL13RA1 gene was associated with COPD and lower FEV1. Conclusion:, These data suggest that IL13 SNPs (promoter and coding region) and, to a lesser extent, IL4RA SNPs may contribute to atopy and asthma. We also provide tentative evidence that IL13 SNPs in the coding region may be of significance in COPD susceptibility. [source] TLR-related pathway analysis: novel gene,gene interactions in the development of asthma and atopyALLERGY, Issue 2 2010N. E. Reijmerink To cite this article: Reijmerink NE, Bottema RWB, Kerkhof M, Gerritsen J, Stelma FF, Thijs C, van Schayck CP, Smit HA, Brunekreef B, Koppelman GH, Postma DS. TLR-related pathway analysis: novel gene,gene interactions in the development of asthma and atopy. Allergy 2010; 65: 199,207. Abstract Background:, The toll-like receptor (TLR)-related pathway is important in host defence and may be crucial in the development of asthma and atopy. Numerous studies have shown associations of TLR-related pathway genes with asthma and atopy phenotypes. So far it has not been investigated whether gene,gene interactions in this pathway contribute to atopy and asthma development. Methods:, One hundred and sixty-nine haplotype tagging single nucleotide polymorphisms (SNPs) of 29 genes (i.e. membrane and intracellular receptors, TLR4 or lipopolysaccharide-binding/facilitating proteins, adaptors, interleukin-1 receptor associated kinases, kinases, chaperone molecules, transcription factors and inhibitors) were analysed for single- and multilocus associations with atopy [total and specific immunglobulin E (IgE) at 1,2 and 6,8 years] and asthma (6,8 years). A total of 3062 Dutch children from the birth cohorts PIAMA, PREVASC and KOALA (Allergenic study) were investigated. Chi-squared test, logistic regression and the data mining approach multifactor dimensionality reduction method (MDR) were used in analysis. Results:, Several genes in the TLR-related pathway were associated with atopy and/or asthma [e.g. IL1RL1, BPI, NOD1, NOD2 and MAP3K7IP1]. Multiple, single associations were found with the phenotypes under study. MDR analysis showed novel, significant gene,gene interactions in association with atopy and asthma phenotypes (e.g. IL1RL1 and TLR4 with sIgE to indoor allergens and IRAK1, NOD1 and MAP3K7IP1 with asthma). Interestingly, gene,gene interactions were identified with SNPs that did not have an effect on their own. Conclusion:, Our unbiased approach provided suggestive evidence for interaction between several TLR-related pathway genes important in atopy and/or asthma development and pointed to novel genes. [source] A novel promoter polymorphism in the gene encoding complement component 5 receptor 1 on chromosome 19q13.3 is not associated with asthma and atopy in three independent populationsCLINICAL & EXPERIMENTAL ALLERGY, Issue 5 2004K. C. Barnes Summary Background The inflammatory functions of complement component 5 (C5) are mediated by its receptor, C5R1, which is expressed on bronchial, epithelial, vascular endothelial and smooth muscle cells. A susceptibility locus for murine allergen-induced airway hyper-responsiveness was identified in a region syntenic to human chromosome 19q13, where linkage to asthma has been demonstrated and where the gene encoding C5R1 is localized. Objective The aim of this study was to screen for novel polymorphisms in the C5R1 gene and to determine whether any identified polymorphisms are associated with asthma and/or atopy and whether they are functional. Methods Single-nucleotide polymorphism (SNP) detection in the gene encoding C5R1 was performed by direct sequencing. Genotyping was performed in three populations characterized for asthma and/or atopy: (1) 823 German children from The Multicenter Allergy Study; (2) 146 individuals from Tangier Island, Virginia, a Caucasian isolate; and (3) asthma case,parent trios selected from 134 families (N=783) in Barbados. Functional studies were performed to evaluate differences between the wild-type and the variant alleles. Results We identified a novel SNP in the promoter region of C5R1 at position ,245 (T/C). Frequency of the ,245C allele was similar in the German (31.5%) and Tangier Island (36.3%) populations, but higher in the Afro-Caribbean population (53.0%; P=0.0039 to <0.0001). We observed no significant associations between the ,245 polymorphism and asthma or atopy phenotypes. Upon examination of the functional consequences of the ,245T/C polymorphism, we did not observe any change in promoter activity. Conclusion This new marker may provide a valuable tool to assess the risk for C5a-associated disorders, but it does not appear to be associated with asthma and/or atopy. [source] | ||||||||||