Overview of Technical Aspects and Chemistries of Next-Generation Sequencing

Clinical genomic testing has been made possible by the development of "next-generation" sequencing (NGS) technologies that allow large quantities of nucleic acid sequence to be obtained in a clinically meaningful time frame. This chapter reviews the sequencing platforms that are currently in most common use, including Illumina, Ion Torrent, SOLiD, and Roche 454. Sanger sequencing is discussed as a "first-generation" technology that retains an important place in clinical genomics for orthogonal validation of NGS findings and for coverage of areas not amenable to NGS.