Fine mapping and single nucleotide polymorphism association results of candidate genes for asthma and related phenotypes
HUMAN MUTATION
Authors: Immervoll, T; Loesgen, S; Dutsch, G; Gohlke, H; Herbon, N; Klugbauer, S; Dempfle, A; Bickeboller, H; Becker-Follmann, J; Ruschendorf, F; Saar, K; Reis, A; Wichmann, HE; Wjst, M
Abstract
Several genome,wide screens for asthma and related phenotypes have been published to date but data on fine,mapping are scarce. For higher resolution we performed a fine-mapping study with 2 cM average spacing in often discussed asthma candidate regions (2p, 5q, 6p, 7p, 9q, 11p, and 12q) to narrow down the regions of interest. All participants of a Caucasian family study (97 families with at least two affected sib pairs) were genotyped for 49 supplementary polymorphic dinucleotide markers. Our results indicate increased evidence for linkage on chromosome 6p, 9q, and 12q. These candidate regions were further analyzed with SNP polymorphisms in the endothelin 1 (EDN1), lymphotoxin alpha (LTA), and neuronal nitric oxide synthase (NOS 1) genes. In addition, IL4-590C>T and IL10-592C>A, localized on chromosomes 5q and 1q, respectively, have been analyzed for SNP association. Of the six SNPs tested, four revealed weak association with the examined phenotypes. These are the IL10-592C>A SNP in the interleukin 10 gene (p=0.036 for eosinophil cell counts), the 4124T>C SNP in EDN1 (p=0.044 for asthma), the 3391C>T SNP in NOS I with eosinophil cell counts (p=0.0086), and the 5266C>T polymorphism, also in the NOS1 gene, for high IgE levels (p=0.022). In summary, fine mapping data enable us to cone fine asthma candidate regions, while variants of EDN1 and NOS1, or nearby genes, may play an important role in this context. Hum Mutat 18:327-336, 2001. (C) 2001 Wiley-Liss, Inc.
microRNA-mRNA regulatory networks underlying chronic mucus hypersecretion in COPD
EUROPEAN RESPIRATORY JOURNAL
Authors: Tasena, Hataitip; Faiz, Alen; Timens, Wim; Noordhoek, Jacobien; Hylkema, Machteld N.; Gosens, Reinoud; Hiemstra, Pieter S.; Spira, Avrum; Postma, Dirkje S.; Tew, Gaik W.; Grimbaldeston, Michele A.; van den Berge, Maarten; Heijink, Irene H.; Brandsma, Corry-Anke
Abstract
Chronic mucus hypersecretion (CMH) is a common feature in chronic obstructive pulmonary disease (COPD) and is associated with worse prognosis and quality of life. This study aimed to identify microRNA (miRNA)-mRNA regulatory networks underlying CMH. The expression profiles of miRNA and mRNA in bronchial biopsies from 63 COPD patients were associated with CMH using linear regression. Potential mRNA targets of each CMH-associated miRNA were identified using Pearson correlations. Gene set enrichment analysis (GSEA) and STRING (search tool for the retrieval of interacting genes/proteins) analysis were used to identify key genes and pathways. 20 miRNAs and 539 mRNAs were differentially expressed with CMH in COPD. The expression of 10 miRNAs was significantly correlated with the expression of one or more mRNAs. Of these, miR-134-5p, miR-146a-5p and the let-7 family had the highest representation of CMH-associated mRNAs among their negatively correlated predicted targets. KRAS and EDN1 were identified as key regulators of CMH and were negatively correlated predicted targets of miR-134-5p and let-7a-5p, let-7d-5p, and let-7f-5p, respectively. GSEA suggested involvement of MUC5AC-related genes and several other relevant gene sets in CMH. The lower expression of miR-134-5p was confirmed in primary airway fibroblasts from COPD patients with CMH. We identified miR-134-5p, miR-146a-5p and let-7 family, along with their potential target genes including KRAS and EDN1, as potential key miRNA-mRNA networks regulating CMH in COPD.