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Separating the Sequencing Products: Transcript

The DNA molecules produced during the sequencing reaction are separated from each other by a process called electrophoresis. DNA molecules are negatively charged. The sequencing machine sets up an electric field; all the DNA moves through a porous gel toward the positive electrode. The gel acts like a sieve; shorter DNA fragments move more quickly through the holes of the gel than do larger DNA fragments.

Last updated: March 29, 2012