The advent of PCR has led to an explosion of microbial gene sequencing in recent years. PCR spells out the entire sequence of the nucleotide bases (the As, Gs, Cs, and Ts) in a DNA molecule that code for a specific protein. Scientists also use sequencing to spell out from start to end every single nucleotide in an organism’s DNA — its entire genome.
Gene and genome sequencing involve a variety of computers, software programs, automated sequencing machines, fluorescent dyes, lasers, and other tools.
The development of machines that can quickly chop up, separate, realign, and read bits of DNA have greatly speeded up the sequencing process. What used to take
a person working by hand to do in a year can now be done by machines in just a few hours. Scientists use gene and genome sequences to precisely compare and differentiate organisms.