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DNA fingerprinting is carried out through several steps. These steps are as follows:

Step 1: Isolating the DNA from the specimen

cells are broken down to release and extract DNA and purified if DNA is relatively small in amount PCR amplification is done to produce millions of copies of a particular DNA sequence.

Step 2: Restriction enzymes

the DNA is cut into fragments using restriction enzymes. Restriction enzymes cuts the DNA at a specific base sequence.

The sections of DNA that are cut out are called restriction fragments.

this step creates thousands of different sizes of restriction fragments.

Step 3: Gel electrophoresis

sorts the DNA pieces by size through the process of gel electrophoresis.

DNA fragments are injected into the wells and an electric current is applied along the gel. DNA is negatively charged therefore the movement of the DNA will be towards the positive end of the gel.

fragments in the gel are separated according to their DNA fragments size.

shorter DNA fragments will move faster than the longer fragments. shorter fragments will be at the lower part of the gel while longer fragments will be towards the upper part of the gel.

Step 4:Denaturing

DNA in the gel is chemically treated by alkali or heated to denature DNA fragments to keep it in single-stranded form.

Step 5: Blotting

A Souther blot is performed to transfer the DNA onto a membrane or the gel is added with a radioactive material which combines with the DNA fragments giving off a fluorescent image. This is now ready to be analysed which will be the last step