Epigenetics is the study of heritable changes in gene expression that occurs without a change in DNA sequence.The development of epigenetics makes up for the insufficiency of classic genetics and promotes the development of genetics.The interrelationship between epigenetics and genetics is like a yin-yang,which are different from each other,and cooperatively take part in regulation of critical biological processes of development and evolution,etc.They constitute the two inseparable parts of genetics.The def...