In bioinformatics, sequence assembly refers to aligning and merging fragments of a much longer DNA sequence in order to reconstruct the original sequence. This is needed as DNA sequencing technology cannot read whole genomes in one go, but rather reads small pieces of between 20 and 1000 bases, depending on the technology used. Typically the short fragments, called reads, result from shotgun sequencing genomic DNA, or gene transcript (ESTs).
The problem of sequence assembly can be compared to taking many copies of a book, passing them all through a shredder, and piecing the text of the book back together just by looking at the shredded pieces. Besides the obvious difficulty of this task, there are some extra practical issues: the original may have many repeated paragraphs, and some shreds may be modified during shredding to have typos. Excerpts from another book may also be added in, and some shreds may be completely unrecognizable.
Read more about Sequence Assembly: Genome Assemblers, EST Assemblers, De-novo Vs. Mapping Assembly, Influence of Technological Changes, Greedy Algorithm, Available Assemblers
Famous quotes containing the words sequence and/or assembly:
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—E.M. (Edward Morgan)
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