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Resolution: standard / high Figure 1.
Comparison of conventional and massively parallel sequence pipelines. Both pipelines
begin with a DNA fragmentation step. (a) The steps in a conventional genome-sequencing pipeline, most of which require dedicated
automation and processing in a 384-well format. DNA fragments are subcloned into bacterial
vectors and introduced into bacterial cells to prepare a library covering the whole
genome. The transformed cells containing subclones are plated and grown and then harvested
by robotic picking, and the DNA from each one is isolated and sequenced. The sequence
is visualized by loading onto a capillary sequencing instrument. (b) The steps in a generic massively parallel genome-sequencing pipeline. Genomic DNA
fragments first undergo end repair to provide blunt ends for adaptor ligation and
then have specific adaptors ligated to their ends that contain priming sites for PCR
and sequencing. The adaptor-ligated fragments are then hybridized to complementary
adaptors that are fixed to a surface (a slide or bead), and then in situ PCR amplification is used instead of bacterial amplification in vivo. Sequencing reactions of the surface-amplified fragments take place on the surface.
The sequence is visualized using either luciferase (pyrosequencing) or fluorescence
reporting that is detected by a CCD camera.
Mardis Genome Biology 2006 7:112 doi:10.1186/gb-2006-7-7-112 |