Advantages and limitations of next-generation sequencing technologies: a comparison of electrophoresis and non-electrophoresis methods.

Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL, USA.
Electrophoresis (Impact Factor: 3.26). 01/2009; 29(23):4618-26. DOI:10.1002/elps.200800456
Source: PubMed

ABSTRACT The reference human genome provides an adequate basis for biological researchers to study the relationship between genotype and the associated phenotypes, but a large push is underway to sequence many more genomes to determine the role of various specificities among different individuals that control these relationships and to enable the use of human genome data for personalized and preventative healthcare. The current electrophoretic methodology for sequencing an entire mammalian genome, which includes standard molecular biology techniques for genomic sample preparation and the separation of DNA fragments using capillary array electrophoresis, remains far too expensive ($5 million) to make genome sequencing ubiquitous. The National Human Genome Research Institute has put forth goals to reduce the cost of human genome sequencing to $100,000 in the short term and $1000 in the long term to spur the innovative development of technologies that will permit the routine sequencing of human genomes for use as a diagnostic tool for disease. Since the announcement of these goals, several companies have developed and released new, non-electrophoresis-based sequencing instruments that enable massive throughput in the gathering of genomic information. In this review, we discuss the advantages and limitations of these new, massively parallel sequencers and compare them with the currently developing next generation of electrophoresis-based genetic analysis platforms, specifically microchip electrophoresis devices, in the context of three distinct types of genetic analysis.

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