Successful completion of the Human Genome Project gave the hope for development of novel therapeutics, diagnostics for the welfare of humankind. Individual genetic studies and genome wide association studies revealed the genetic risk factors for various diseases which can be used in predetermination. This eventually led to the growth of pharmacogenomics that confers individual drug dosage adjustment preventing from adverse effects. However, it addresses only the hitches raised by the underlying genetic sequence but not external factors that influences the genotypic and phenotypic expression. Epigenetic research deals with these factors and studies the modifications caused along with their phenotype. These modifications are reversible which can be used as target for therapeutics, thus improving the treatment strategies of various diseases. In this review, we attempt to discuss the use of epigenetic modifications as drug targets and their mechanism of action.
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