Describe and discuss the diverse ways in which the development of Essay

Describe and discuss the diverse ways in which the development of second generation sequencing technologies has extended the fie - Essay Example On the same note, the four components related to barcoding include specimens, laboratory analysis, database and data analysis (CBOL Plant Working Group 2009, p.12794). Since early 90s, DNA sequencing has involved the use of capillary-based and semi-automated techniques related to Sanger biochemistry. The process of DNA sequencing then involved two approaches that include shotgun sequencing and PCR amplification. Shotgun sequencing involves a process of cloning DNA that through a random fragmentation and transformed into high-copy-number plasmid that is used for changing Escherichia coli. PCR amplification, on the other hand involves a process of targeted resequencing where primers are used to flank the target. Following three decades of improvements, the Sanger biochemistry, is now applied to obtain read lengths that average 1000 bp and accuracies in regard to per base raw that average 99.999%(Hutchison 2007, pp.6227-6237). However, the introduction of second generation sequencing te chniques continues to expand the field of DNA barcoding beyond the Sanger sequencing technique. The second-generation technologies have contributed to alternative DNA barcoding strategies and can be grouped in a number of categories. This includes sequencing using hybridization, cyclic-array sequencing, microelectrophoretic techniques and observation of single molecules in real-time (Healy 2007; Shendure 2005; Soni & Meller 2007). Second generation technologies as used in the field of barcoding implies to the different types of sequencing that have been introduced recently, in a commercial product and includes 454 sequencing, Solexa technology, Heliscope technology of single molecule sequencer, the Polonator and the SoLiD platform. These products have improved the diversity of sequencing, and have helped in the application of alternative protocols for purposes of generating jumping libraries related to mate-paired tags that contain controlled distance distributions. Further, these n ew technologies through various approaches, permits the production of amplicons that are clonally clustered, and acts as sequencing features. A common feature among the second-generation technologies in DNA barcoding is that, PCR amplicons emanating from various single library molecules can be spatially clustered on a single site within a planar substrate or on micron-scale bead’s surface. The sequencing process has further improved because of the introduction of alternating cycles related to enzymes-based biochemistry and data acquisition that is based on imaging (Mitra et al. 2003, pp. 55-62). In essence, the benefits of the second-generation technologies in comparison to the Sanger technique in diversifying DNA barcoding includes, the introduction of in vitro construction related to sequencing library. This is followed by cloning amplifications that produce sequencing features and circumvent numerous bottlenecks considered affecting parallelism related to sequencing consid ered as conventional. Second generation technologies compared to Sanger sequencing, have an advantage in terms of introducing array-based sequencing. Because of the existence of an array-based sequencing, the process of DNA barcoding is able to realize a considerable degree of parallelism compared to capillary-based sequencing.