The DNA Synthesis: Fred Sanger Method

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In Fred Sanger Method, the DNA to be sequenced serves as a template for DNA synthesis. A DNA primer is needed which is designed to be a starting point or the initiating point for DNA synthesis on the strand of the DNA to be sequenced. The primer is hydrogen bonded to the 3 ' end of the DNA to be sequenced. The DNA with the primer is divided into four separate reaction mixtures. Each reaction mixture contains all four dNTPs and in addition, one of the four dideoxy analogs (dideoxyribonucleoside triphosphates ddNTPs) of the deoxyribonucleoside triphosphates. When a ddNTP is incorporated into a chain of nucleotides, synthesis terminates. This is because the ddNTP molecule lacks a 3 ' hydroxyl group (instead of hydroxyl group, it has only