In the current form of dideoxy DNA sequencing,the primer is unlabeled and each dideoxynucleotide is labeled with a different fluorescent marker.This method _____.
A)eliminates the need to run sequencing reaction products on a gel
B)allows a DNA sequence to be determined from four separate sequencing reactions,each run on a separate lane of a gel
C)allows a DNA sequence to be determined from one sequencing reaction that is run on a single lane of a gel
D)eliminates the need for sophisticated machines to read the output of each sequencing reaction

Question

Quizplus · Accepted Answer

In the current form of dideoxy DNA sequencing, the reaction products are run on a single lane of a gel, and each dideoxynucleotide is labeled with a different fluorescent marker. Therefore, a DNA sequence can be determined from one sequencing reaction that is run on a single lane of a gel. Option A is incorrect because gel electrophoresis is still required to separate the reaction products by size. Option B is incorrect because all four dideoxynucleotides are included in a single reaction tube, and only one lane of the gel is required. Option D is incorrect because sophisticated machines are still necessary to detect the fluorescent signals from the labeled dideoxynucleotides.

In the Current Form of Dideoxy DNA Sequencing,the Primer Is