Question

You use the Sanger sequencing protocol to sequence the following DNA fragment: 5’-TGCACGGGTCAGCT-(primer site)-3’ Draw a picture of the resulting sequencing gel, with products ending in each of the four dideoxynucleotides (ddATP, ddTTP, ddCTP, and ddGTP) in separate lanes of the gel. Be sure to label each lane as ddATP, ddTTP, ddCTP, or ddGTP.

Answer 1

The classical chain-termination method requires a single-stranded DNA template, a DNA primer, a DNA polymerase, normal deoxynucleosidetriphosphates (dNTPs), and modified di-deoxynucleotidetriphosphates (ddNTPs), the latter of which terminate DNA strand elongation. These chain-terminating nucleotides lack a 3'-OH group required for the formation of a phosphodiester bondbetween two nucleotides, causing DNA polymerase to cease extension of DNA when a modified ddNTP is incorporated.

the given sequence gel will look like this