Epigenetics is turning out to be one of the promising studies in cancer research. This review focuses mainly on how genetic and epigenetic factors like DNA methylation, histone modifications and various other genes can assess the promoter region of cancer related genes and provides a tool for cancer diagnosis and research. The objective of the review is to provide an overview of the literature with some recent developments providing insights into the important question of co-evolution of epigenetic changes in breast cancer progression and tumorigenesis. This review also comply study of different genetic changes existing in breast cancer. Further in this review focus on functioning of DNA methylation, including both normal, disruptions or abnormal role in human disease, and changes in DNA methylation during human breast cancer is also noted.