Shotgun and Next-generation Sequencing
The classical shotgun sequencing was based on the Sanger sequencing method: this was the most advanced technique for sequencing genomes from about 1995–2005. The shotgun strategy is still applied today, however using other sequencing technologies, called next-generation sequencing. These technologies produce shorter reads (anywhere from 25–500bp) but many hundreds of thousands or millions of reads in a relatively short time (on the order of a day). This results in high coverage, but the assembly process is much more computationally expensive. These technologies are vastly superior to Sanger sequencing due to the high volume of data and the relatively short time it takes to sequence a whole genome. The major disadvantage is that the accuracies are usually lower (although this is compensated for by the high coverage).
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