Question

Sanger sequencing allows the identification of the bases and their order in a target piece of DNA. This technique exploits the way DNA is transcribed by using a primer and allowing new DNA to be created from its 3' end. In this technique, DNA is manufactured in vitro, which means that enzymes and molecules are combined in a test tube to allow the reactions to occur. In the original technique, four tubes were prepared, each containing the same reactants, but each is spiked with a very small quantity of different dNTPs which end on that base. The fragments created are thus of different sizes and these are separated using gel electrophoresis. Large bands represent the 5' ends of the fragments and are found near the bottom of the gel. AT GG

Answer 1

Sanger sequencing method is used to find the sequence of unknown DNA.

In this method, the primers are used. The primer binds to the unknown DNA. Now, nucleotide bases are added. In this way, there is found synthesis of DNA.

After that at the end dinucleotidw are added to the reaction tube for stoppimg the DNA synthesis.

Every nucleotide has different color. The newly synthesized strand is run on the gel. The 5" End side is found at the bottom and 3' end is found at upper side of gel.

Now the complementary sequence of newly synthesised DNA is the sequence of unknown DNA.