What are the different Next Generation Sequencing (NGS) technologies?

Some of the most widely used Next Generation Sequencing (NGS) technologies include:

Pyrosequencing: Pyrosequencing is based on the detection of pyrophosphate that is released on adding nucleotides to the DNA chain. It is one of the earliest next generation sequencing methods.

Ion Torrent Semiconductor Sequencing: Ion torrent semiconductor sequencing is based on the detection of hydrogen ions that are produced during DNA polymerization. In this method, a new DNA strand, complementary to the target strand, is synthesized one base at a time. Ion torrent semiconductor sequencing is faster and more cost-effective than most other methods. The downside is the difficulty in enumerating the number of identical bases that are added consecutively. 

Sequencing By Ligation (SOLiD): Sequencing by ligation uses DNA ligase to detect the nucleotide present at a specific position in a DNA sequence. DNA ligase is a widely-used enzyme for ligating double stranded DNA strands. It is a highly accurate and cost-effective NGS technology. The downside is its limited application because of its short read lengths.

Reversible Terminator Sequencing (Illumina): Reversible terminator sequencing uses modified nucleotides in reversible termination of the primer extension. This is unlike the traditional Sanger technology in which the primer extension is terminated irreversibly. The combination of short inserts and longer reads in reversible terminator sequencing enhances the ability to fully characterize any genome. The major advantage of this technology is that it results in accurate data for a broad range of applications.