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Optical mapping is a technique for constructing ordered, genome-wide, high-resolution restriction maps from single, stained molecules of DNA, called "optical maps". By mapping the location of restriction enzyme sites along the unknown DNA of an organism, the spectrum of resulting DNA fragments collectively serve as a unique "fingerprint" or "barcode" for that sequence. Originally developed by Dr. David C. Schwartz and his lab at NYU in the 1990s 〔Schwartz, D. C., et al. "Ordered Restriction Maps of Saccharomyces Cerevisiae Chromosomes Constructed by Optical Mapping." Science (New York, N.Y.) 262.5130 (1993): 110–4.〕 this method has since been integral to the assembly process of many large-scale sequencing projects for both microbial and eukaryotic genomes. ==Technology== The modern optical mapping platform works as follows〔Dimalanta, E.T. ''et al.'' A microfluidic system for large DNA molecule arrays. Anal. Chem. 76 (2004): 5293–5301.〕 #Genomic DNA is obtained from lysed cells, and randomly sheared to produce a "library" of large genomic molecules for optical mapping. #A single molecule of DNA is stretched (or elongated) and held in place on a slide under a fluorescent microscope due to charge interactions. #DNA molecule is digested by added restriction enzymes, which cleave at specific digestion sites. The resulting molecule fragment remain attached to the surface. The fragment ends at the cleavage site are drawn back (due to elasticity of linearized DNA), leaving gaps which are identifiable under the microscope as gaps. #DNA fragments stained with intercalating dye are visualized by fluorescence microscopy and are sized by measuring the integrated fluorescence intensity. This produces an optical map of single molecules. #Individual optical maps are combined to produce a consensus, genomic optical map. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「optical mapping」の詳細全文を読む スポンサード リンク
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