In recent years, significant progress has been made in identifying genetic factors that underlie some common complex diseases, enabled by approaches such as genome-wide association studies. Despite this progress, most factors that determine risk in complex diseases remain unknown, leading to an interest in nongenetic factors that contribute to disease. Epigenetics is an emerging field, studying changes in the regulation of gene expression that are not a result of changes to the primary DNA sequence itself. It is through these changes that the environment might modulate genetic predisposition to disease. In November 2010, Science published a special issue of review and perspective articles devoted to the emerging field of epigenetics (volume 330, No. 6004, Fall 2010).
Nickells RW, Merbs SL. The Potential Role of Epigenetics in Ocular Diseases. Arch Ophthalmol. 2012;130(4):508-509. doi:10.1001/archopthalmol.2011.1423