The determination of the exact order of nucleotides in DNA is accomplished by....?

Question

The determination of the exact order of nucleotides in DNA is accomplished by....?

Answer 1

this process is called sanger sequencing,  and basically what it does is radiolabel (label DNA with a radioactive nucleotide) DNA  which ceases DNA replication/elongation.  

So what do you need in order to do this experiment.   well,  you need a single stranded template strand of DNA (yes using PCR techniques such as incubation times with different temperature settings is one way of doing this) and your 4 nucleotides,  but one of them,  say adenine is radioactive (via conjugation of some radioactive iodine for example).   what  this means is that every time one of these A is incorporated into the DNA strand it will stop growing, and you will end up with a bunch of fragments of DNA  at different sizes,  and with some clever detective work using sizes or computer programs,   you can put together the puzzle.

Now fancy new technology allows us to do this using concentrations of each nucleotide being radiolabled  and coming up with more prescise sequencing standards.

Answer 2

DNA Sequencing

Answer 3

First you would perform a PCR reaction to amplify the specific part of the genome you want.  Then, with this massive amount of individual sample, you use special chemicals that insert at specific individual bases (ie, adds at Adenine, Cytosine, Guanine or Thymine).  This leaves the sample with many different length fragments, which can then be separated through electrophoresis.  The chemicals used are also fluorescent.  This allows a computer to read which base is which as it comes off the sample.  These results are combined to give the linear order of bases.