Chromatin and heritability: how epigenetic studies can complement genetic approaches

Despite the success in using genome-wide association studies to identify many loci associated with human disease, there are several gaps in understanding of how common genetic diseases are manifested. Epigenetic studies, which focus on DNA and chromatin modifications, have the potential to complement genetic approaches and provide more insight into mechanism, environmental effects and modes of inheritance, including the potential for non-DNA-based heritability. However, there are considerable challenges in designing and interpreting epigenetic studies associated with disease. Here, I review recent studies focused on individual variation in chromatin, and outline how epigenome-based studies can be used to complement genetic studies. In particular, I see more benefit to epigenetic studies being performed in the context of genetic studies, rather than as separate investigations.