Differential methylation pattern in patients with coronary artery disease: pilot study

Area of Science:

• Genetics
• Epigenetics
• Cardiovascular Disease Research

Background:

• Coronary artery disease (CAD) is highly heritable, but genetic factors alone do not fully explain its etiology.
• Epigenetic alterations, such as DNA methylation, are increasingly recognized as crucial in CAD pathophysiology.
• DNA methylation patterns can influence gene expression involved in CAD development.

Purpose of the Study:

• To identify differentially methylated regions (DMRs) in the genomes of CAD patients using a high-coverage microarray.
• To explore the role of DNA methylation in the development of CAD.
• To investigate potential epigenetic biomarkers for CAD.

Main Methods:

• Epigenome-wide analysis of DNA methylation in whole blood from six male CAD patients and six matched controls using Illumina's Infinium HumanMethylation450 BeadChip.
• Identification of DMRs using Illumina's GenomeStudio software.
• Pathway and gene ontology analysis using DAVID (Database for Annotation, Visualisation and Integrated Discovery).

Main Results:

• A total of 429 significant DMRs were identified, with 222 hypomethylated and 207 hypermethylated.
• Antigen processing and presentation emerged as the most significant biological pathway (p=4.35×10⁻⁵).
• Specific HLA genes (HLA-DRB1, HLA-DQA1, HLA-DQB1, HLA-G, HLA-C) were implicated in triggering inflammatory pathways.

Conclusions:

• This pilot study provides evidence for significant DNA methylation differences in CAD patients.
• The identified DMRs, particularly those in antigen processing and presentation pathways, offer potential insights into CAD etiology.
• This research represents the first high-coverage microarray study of DMRs in CAD patients in India.