Denaturing gradient gel electrophoresis 

Denaturing gradient gel electrophoresis - also known as DGGE is widely used to study variations in the DNA. In this method a gel is prepared with denaturant. The gel is prepared in such a way that the concentration of denaturant changes from one end of the gel to another. As the DNA moves from top to the bottom of the gel, it gradually denatures. Now if there are variations in the DNA sample, then there will be difference in migration in the gel, due to different melting profile.