Overview of DNA Sequencing Strategies

Department of Genome Sciences, University of Washington, Seattle, Washington, USA.
Current protocols in molecular biology / edited by Frederick M. Ausubel ... [et al.] 10/2011; Chapter 7:Unit7.1. DOI: 10.1002/0471142727.mb0701s96
Source: PubMed


Efficient and cost-effective DNA sequencing technologies are critical to the progress of molecular biology. This overview of DNA sequencing strategies provides a high-level review of seven distinct approaches to DNA sequencing: (a) dideoxy sequencing; (b) solid phase sequencing; (c) sequencing-by-hybridization; (d) mass spectrometry; (e) cyclic array sequencing; (f) microelectrophoresis; and (g) nanopore sequencing. Other platforms currently in development are also briefly described. The primary focus here is on Sanger dideoxy sequencing, which has been the dominant technology since 1977, and on cyclic array strategies, for which several competitive implementations have been developed since 2005. Because the field of DNA sequencing is changing rapidly, this unit represents a snapshot as of September, 2011.

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    • "are expanding analyses of sequence variations by including individuals in many other human populations. Resequencing of more genomes is now possible because new sequencing technologies are reducing the cost and increasing the throughput (Bennett et al., 2005; Shendure et al., 2008). Creating a more in-depth coverage of human genetic diversity is necessary for identifying causative SNPs or other genetic variation and to account for epistasis (see above). "
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    • "Next-generation sequencing can be defined as any number of new technologies that promise to dramatically increase the speed and reduce the cost of DNA sequencing when compared to traditional Sanger sequencing. Technologies include currently commercial pyrosequencing and mass spectroscopy based platforms to the developing field of nanopore sequencing (Hall 2007; Shendure et al. 2008). While whole genome sequencing is not at the time of writing cost competitive for the discovery of the approximately several hundred induced mutations in a highly mutagenized diploid plant in a popUlation of thousands of plants, progress is being made in strategies for selective enrichment of desired targets that drive costs downward. "
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