Sequencing Strategies and Tactics in DNA and RNA Analysis
Nucleic Acids Structure and Mapping
Published Online: 15 SEP 2006
Copyright © 2000 John Wiley & Sons, Ltd. All rights reserved.
Encyclopedia of Analytical Chemistry
How to Cite
Azhikina, T. L. 2006. Sequencing Strategies and Tactics in DNA and RNA Analysis. Encyclopedia of Analytical Chemistry. .
- Published Online: 15 SEP 2006
Sequencing procedures are aimed at the determination of sequences of monomer units constituting linear biopolymer molecules. In the particular case of nucleic acids the monomer units are DNA or RNA residues. The present article reviews several sequencing strategies: different approaches (random or systematic sequencing) as well as their combinations giving the best results for long-range sequencing applicable to long and unique DNA fragments, including entire genomes, up to the Homo sapiens genome size; massive sequencing of relatively short fragments such as RNAs, complementary DNAs (cDNAs), etc.; and comparative sequencing of related DNA fragments originating from various individuals or different species.
Although particular sequencing approaches may involve different ways of DNA treatment (chemical, enzymatic, or physical), they are all based on the same idea: a labeled molecule is cut to obtain a set of fragments all having one common end, other ends being different owing to the statistical character of the nucleic acid chain cleavage. The fragments obtained are then separated according to their lengths.
The primary structure of nucleic acids is a key not only to physical and chemical properties of the molecules but also to the biological (genetic) information therein, including structures of genes and proteins, the ways of gene regulation and cell response to different signals. This is a great advantage over other physical, chemical, or biological methods of DNA/RNA analysis. However, sequencing in itself is usually insufficient to predict unambiguously the biological properties and functions of the encoded products.