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DNA code construction refers to the application of coding theory to the design of nucleic acid systems for the field of DNA–based computation. ==Introduction== DNA sequences are known to appear in the form of double helices in living cells, in which one DNA strand is hybridized to its complementary strand through a series of hydrogen bonds. For the purpose of this entry, we shall focus on only oligonucleotides. DNA computing involves allowing synthetic oligonucleotide strands to hybridize in such a way as to perform computation. DNA computing requires that the self-assembly of the oligonucleotide strands happen in such a way that hybridization should occur in a manner compatible with the goals of computation. The field of DNA computing was established in Leonard M. Adelman’s seminal paper. His work is significant for a number of reasons: * It shows how one could use the highly parallel nature of computation performed by DNA to solve problems that are difficult or almost impossible to solve using the traditional methods. * It's an example of computation at a molecular level, on the lines of nanocomputing, and this potentially is a major advantage as far as the information density on storage media is considered, which can never be reached by the semiconductor industry. * It demonstrates unique aspects of DNA as a data structure. This capability for massively parallel computation in DNA computing can be exploited in solving many computational problems on an enormously large scale such as cell-based computational systems for cancer diagnostics and treatment, and ultra-high density storage media. This selection of codewords (sequences of DNA oligonucleotides) is a major hurdle in itself due to the phenomenon of secondary structure formation (in which DNA strands tend to fold onto themselves during hybridization and hence rendering themselves useless in further computations. This is also known as self-hybridization). The Nussinov-Jacobson algorithm is used to predict secondary structures and also to identify certain design criteria that reduce the possibility of secondary structure formation in a codeword. In essence this algorithm shows how the presence of a cyclic structure in a DNA code reduces the complexity of the problem of testing the codewords for secondary structures. Novel constructions of such codes include using cyclic reversible extended Goppa codes, generalized Hadamard matrices, and a binary approach. Before diving into these constructions, we shall revisit certain fundamental genetic terminology. The motivation for the theorems presented in this article, is that they concur with the Nussinov - Jacobson algorithm, in that the existence of cyclic structure helps in reducing complexity and thus prevents secondary structure formation. i.e. these algorithms satisfy some or all the design requirements for DNA oligonucleotides at the time of hybridization (which is the core of the DNA computing process) and hence do not suffer from the problems of self - hybridization. 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「Coding theory approaches to nucleic acid design」の詳細全文を読む スポンサード リンク
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