Moving towards third-generation sequencing technologies

Within just the past few years, next-generation sequencing (NGS) platforms have reduced the cost of DNA sequencing by several orders of magnitude. With these lower costs, DNA sequencing is increasingly powerful as a single-data format onto which a broad range of biological processes can be projected for high-throughput molecular profiling. Although significant challenges remain, translating these powerful technologies into useful laboratory tests has great potential. This chapter provides a comparative analysis of currently available NGS techniques, including those of Illumina, 454/Roche, Applied Biosystems, and Helicos BioSciences, and addresses emerging techniques, such as Pacific Biosciences single-molecule sequencing and nanopore sequencing. Furthermore, very recent electronic sequencing from Ion Torrent is elaborated. The chapter discusses advantages and disadvantages of individual platforms, and those common to all techniques, including template preparation and genome enrichment.