The EWAS Catalog: a database of epigenome-wide association studies
Thomas Battram, Paul Yousefi, Gemma Crawford, C. Leeson Prince, Mahsa Sheikhali Babei, Gemma C. Sharp, Charlie Hatcher, María Jesús Vega‐Salas, Sahar Khodabakhsh, Oliver Whitehurst, Ryan Langdon, L. Meghan Mahoney, Hannah R. Elliott, Giulia Mancano, Matthew A. Lee, Sarah Watkins, Abigail C. Lay, Gibran Hemani, Tom R. Gaunt, Caroline L. Relton, James R Staley, Matthew Suderman
Abstract
Epigenome-wide association studies (EWAS) seek to quantify associations between traits/exposures and DNA methylation measured at thousands or millions of CpG sites across the genome. In recent years, the increase in availability of DNA methylation measures in population-based cohorts and case-control studies has resulted in a dramatic expansion of the number of EWAS being performed and pub-lished. To make this rich source of results more accessible, we have manually curated a database of CpG-trait associations (with p<1x10-4) from published EWAS, each assaying over 100,000 CpGs in at least 100 individuals. From 2021-01-29, The EWAS Catalog contained 1,045,303 associations from over 1000 EWAS. This includes 652,530 associations from 264 peer-reviewed publications. In addi-tion, it also contains summary statistics for 392,773 associations from 428 EWAS, performed in data from the Avon Longitudinal Study of Parents and Children (ALSPAC) and the Gene Expression Om-nibus (GEO). The database is accompanied by a web-based tool and R package, giving researchers the opportunity to quickly and easily query EWAS associations and gain insight into the molecular under-pinnings of disease as well as the impact of traits and exposures on the DNA methylome. The EWAS Catalog is available at: http://www.ewascatalog.org.