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Sequencing Methods

320 bytes removed, 17:35, 1 December 2018
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<p>This problem has been addressed with the use of modified DNA polymerase enzyme systems and dyes that minimize incorporation variability, as well as methods for eliminating &quot;dye blobs&quot;. The dye-terminator sequencing method, along with automated high-throughput DNA sequence analyzers, was used for the vast majority of sequencing projects until the introduction of Next Generation Sequencing.</p>
<h3>Automation and sample preparation[<a href="https://en.wikipedia.org/w/index.php?title=Sanger_sequencing&amp;action=edit&amp;section=3" title="Edit section: Automation and sample preparation">edit</a>]</h3>
<p><a href="https://en.wikipedia.org/wiki/File:Sanger_sequencing_read_display.png"><img alt="" src="https://upload.wikimedia.org/wikipedia/commons/thumb/9/98/Sanger_sequencing_read_display.png/220px-Sanger_sequencing_read_display.png" style="height:51px; width:220px" /></a></p>
<p>A polymerase sequences the complementary strand on top of the arched strand. They separate, and the 3&#39; end of each strand is blocked. The forward strand is washed away, and the process of sequence by synthesis repeats for the reverse strand.</p>
<h3>Data analysis[<a href="https://en.wikipedia.org/w/index.php?title=Illumina_dye_sequencing&amp;action=edit&amp;section=8" title="Edit section: Data analysis">edit</a>]</h3>
<p>The sequencing occurs for millions of clusters at once, and each cluster has ~1,000 identical copies of a DNA insert.<sup><a href="https://en.wikipedia.org/wiki/Illumina_dye_sequencing#cite_note-Morozova-10">[10]</a></sup>&nbsp;The sequence data is analyzed by finding fragments with overlapping areas, called&nbsp;<a href="https://en.wikipedia.org/wiki/Contig" title="Contig">contigs</a>, and lining them up. If a reference sequence is known, the contigs are then compared to it for variant identification.</p>