|MadSci Network: Molecular Biology|
Sequnced DNA is end labled with dideoxynucleotide with a radioactive phosphate. When the labeled DNA is separated by polyacrylamide gel electrophoresis, the sequencing products are separated based on their size. Products which have terminated short will run faster in the gel. Following separation the pruducts all need to be uniformly labeled to give a banding pattern of even intensity. Each product will only be labeled once at its end, therefore each product should be able to be visualized equally. The incorporated radioactive nucleotides enable the DNA to be visualized using X-ray film which is very sensitive. Sambrook, Fritcsh, and Maniatis, Molecular Cloning, A Laboratory Manual, 1989, page 13.5-13.7
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