Gel Electrophoresis
Tool or technique that separates large molecules (DNA, protein etc) on the basis of size
(plus electrical charge and other properties. )
To prepare DNA for gel electrophoresis, cut DNA into smaller pieces by:
1. Restriction digestion ( with restriction enzymes) or
2. Amplifying specific STRs by PCR.
Mixtures of different sizes of DNA loaded in wells,
in gel.
Gel covered with buffer solution
DNA samples mixed with dye ( or radioactive
probes attached )
Electrodes attached and turned on
DNA moves through the gel – smallest fragments
move furthest.
GEL IS VISUALISED
Dyes – methylene blue
or ethidium bromide
Southern Blotting with
probes to make an
electroradiograph