Name: Sarajane L Burr
How do you read DNA?
There are two general strategies to sequencing (reading ) DNA.
One way is to break the DNA down piece by piece one or a few bases
at a time but this is not a very efficient way. Most sequencing today
is done using enzymes that make copies of the DNA one bases at a time.
For instance, if you had a piece of DNA that was 100 bases long, using enzyme
you would make a replica that was one base, two bases , three bases...
up to 100 hundred bases long. These replicas would end in one of the
four bases that make up DNA: A,G,C, or T. Each of these replicas
traditionally was made to be radioactive and they were separated in a thin
sheet of plastic between to glass plates. by electricity (electrophoresis).
When the plates are separated a sheet of film is placed on the plastic
gel. When developed, there are bands that can be read to give the
sequence. Many laboratories today use fluorescent labeling of the
DNA and machines can detect a specific bases by there emission spectrum.
A molecular biology text book will supply you a nice diagram explaining
this in a much simpler way. GOOD LUCK!!!
Michael B Lomonaco
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Update: June 2012