Twins are ideal in epigenetic research, because they are natural controls for genetic background, as well as many parental and environmental effects. Epigenetic studies of twins can provide insights into epigenetic heritability, for example, using DNA methylation patterns as a dynamic quantitative trait.
Current research in monozygotic twins with high discordance rates for common diseases suggests that underlying environmental or epigenetic factors may be involved. Epigenetic studies in disease-discordant monozygotic twins demonstrate the power of this design to successfully identify epigenetic changes associated with common complex disease traits.
The Department of Twin Research (DTR) in conjunction with the Beijing Genomics Institute has embarked on a large-scale epigenetic study of 5,000 adult twins (EpiTWIN). The aim of this study is to use whole genome methylation sequencing to improve our understanding of how genetic and environmental factors can impact on epigenetics and how DNA methylation pattern variation can affect a wide range of complex traits.
This study first explores the heritability and genomic biology of DNA methylation patterns within a large scale family design. Secondly, the function of the changes can be explored using multiple datasets on the same individuals using an integrated omics approach including - the Multiple Human Tissue Expression Resource (MuTHER) and the EU EuroBats project providing RNA array and sequencing, and the UK10K project providing DNA whole genome sequence and exomes. In addition we can analyse metabolomics, glycomics and microbiomes on the same twins. We also investigate the DNA methylation and expression patterns within a number of different tissues including blood, skin, adipose and different regions of the brain. Examples of recent integrated EWAS analysis like pain sensitivity, cancer, depression and diabetes will be presented.
www.epitwin.eu