The term DNA sequencing actually refers to the sequencing method that used to determine the arrangement of nucleotide bases (adenine, guanine, cytosine, thymine) in the DNA.
At our center we are using the Dye-Terminator Sequencing which is developed by Frederik Sanger . The term Dye-Terminator Sequencing which means that each of the four di-deoxynucleotide chain terminators are labeled with fluorescent dyes. Each of dye will reflect different color of light when it gets excited by the laser. The labeled DNA fragments are actually subjected to electrophoresis through our high-throughput ABI 3730xl Genetic Analyzer. As a result, 4 different colors are actually observed during the electrophoresis process, and the 4 different colors represent the 4 different nucleotide bases found in DNA.