Sanger Method of DNA Sequencing:
Example 1

Sanger Method of DNA Sequencing

Example 2

The image below shows the separation of DNA fragments of varying lengths by gel electrophoresis. Each lane of the gel (A, C, G, T) contains fragments of DNA which include "chain terminating" dideoxy analogues of the four nucleotides: ddATP, ddCTP, ddGTP, and ddTTP. The smallest fragments have travelled furthest down the gel from the negative to the positive end. A small fragment indicates that a dideoxy nucleotide attached early and prevented any other nucleotides from bonding after that.

Your task is to determine the DNA sequence for the original template DNA strand used in the experiment. Read the gel to obtain the DNA sequence. Then make the complementary strand and check your answer.

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