Dataset Information

Identification of novel differentially methylated sites with potential as clinical predictors of impaired respiratory function and COPD.

ABSTRACT:

Background

The causes of poor respiratory function and COPD are incompletely understood, but it is clear that genes and the environment play a role. As DNA methylation is under both genetic and environmental control, we hypothesised that investigation of differential methylation associated with these phenotypes would permit mechanistic insights, and improve prediction of COPD. We investigated genome-wide differential DNA methylation patterns using the recently released 850?K Illumina EPIC array. This is the largest single population, whole-genome epigenetic study to date.

Methods

Epigenome-wide association studies (EWASs) of respiratory function and COPD were performed in peripheral blood samples from the Generation Scotland: Scottish Family Health Study (GS:SFHS) cohort (n?=?3781; 274 COPD cases and 2919 controls). In independent COPD incidence data (n?=?149), significantly differentially methylated sites (DMSs; p?-8) were evaluated for their added predictive power when added to a model including clinical variables, age, sex, height and smoking history using receiver operating characteristic analysis. The Lothian Birth Cohort 1936 (LBC1936) was used to replicate association (n?=?895) and prediction (n?=?178) results.

Findings

We identified 28 respiratory function and/or COPD associated DMSs, which mapped to genes involved in alternative splicing, JAK-STAT signalling, and axon guidance. In prediction analyses, we observed significant improvement in discrimination between COPD cases and controls (p?InterpretationIdentification of novel DMSs has provided insight into the molecular mechanisms regulating respiratory function and aided prediction of COPD risk. Further studies are needed to assess the causality and clinical utility of identified associations. FUND: Wellcome Trust Strategic Award 10436/Z/14/Z.

SUBMITTER: Bermingham ML

PROVIDER: S-EPMC6557748 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Publications

Identification of novel differentially methylated sites with potential as clinical predictors of impaired respiratory function and COPD.

Bermingham Mairead L ML Walker Rosie M RM Marioni Riccardo E RE Morris Stewart W SW Rawlik Konrad K Zeng Yanni Y Campbell Archie A Redmond Paul P Whalley Heather C HC Adams Mark J MJ Hayward Caroline C Deary Ian J IJ Porteous David J DJ McIntosh Andrew M AM Evans Kathryn L KL

EBioMedicine 20190329

<h4>Background</h4>The causes of poor respiratory function and COPD are incompletely understood, but it is clear that genes and the environment play a role. As DNA methylation is under both genetic and environmental control, we hypothesised that investigation of differential methylation associated with these phenotypes would permit mechanistic insights, and improve prediction of COPD. We investigated genome-wide differential DNA methylation patterns using the recently released 850 K Illumina EPI ...[more]

PMID: 30935889

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Dataset Information

Identification of novel differentially methylated sites with potential as clinical predictors of impaired respiratory function and COPD.

Background

Methods

Findings

Publications

Identification of novel differentially methylated sites with potential as clinical predictors of impaired respiratory function and COPD.

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