Sanger method in principle: modified dideoxy bases are used to cause random terminations during DNA replication. Imagine 4 seperate wells: 1 with modified A's, 1 with modified T's,...
If you start replication in well one you will get lots of DNA strands with different length each ending on A (there are unmodified A's too, each strand cannot be elonged as soon as a modified A is appended, and because you produce lots of copies u can be sure that u will get each fragment of your DNA that ends in an A). Do this for each well (A,C,T,G) and sort them by length (ie. by Gel Electrophoresis). In the gel the 4 wells (A,C,T,G) stay seperated, so u have one line with all fragments ending with A, one with bands for all fragments ending in C... Look for the highest band (shortest fragment) and see to which well it belonged, ie. highest band was a C -> your DNA sequence starts with a C, lookup next highest (ie. a G -> so your DNA is: CG) a.s.o.
Hope that this is simple enough (english isn't my mother tongue).
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Venter sequenced by a modified Sanger / strand termination technique (ie. see: http://www.dnalc.org/resources/animations/sangerse...
Sanger method in principle: modified dideoxy bases are used to cause random terminations during DNA replication. Imagine 4 seperate wells: 1 with modified A's, 1 with modified T's,...
If you start replication in well one you will get lots of DNA strands with different length each ending on A (there are unmodified A's too, each strand cannot be elonged as soon as a modified A is appended, and because you produce lots of copies u can be sure that u will get each fragment of your DNA that ends in an A). Do this for each well (A,C,T,G) and sort them by length (ie. by Gel Electrophoresis). In the gel the 4 wells (A,C,T,G) stay seperated, so u have one line with all fragments ending with A, one with bands for all fragments ending in C... Look for the highest band (shortest fragment) and see to which well it belonged, ie. highest band was a C -> your DNA sequence starts with a C, lookup next highest (ie. a G -> so your DNA is: CG) a.s.o.
Hope that this is simple enough (english isn't my mother tongue).