'''DNA computing''' is a form of Computing which uses DNA and Molecular_biology, instead of the traditional silicon-based Computer technologies. A single gram of DNA with volume of 1 cm³ can hold as much information as a trillion compact discs, approximately 750 Terabytes. This field was initially developed by Leonard_Adleman of the University_of_Southern_California. In 1994, Adleman demonstrated a Proof-of-concept use of DNA as form of computation which was used to solve the seven-point Hamiltonian_path_problem. Since the initial Adleman experiments, advances have been made, and various Turing_machines have been proven to be constructable. There are works over one dimensional lengths, bidimensional tiles, and even three dimensional DNA graphs processing. On April_28 2004, Ehud_Shapiro and researchers at the Weizmann_Institute announced in the journal Nature that they had constructed a DNA computer. This was coupled with an input and output module and is capable of diagnosing Cancerous activity within a cell, and then releasing an anti-cancer drug upon diagnosis. DNA computing is fundamentally similar to Parallel_computing -- we take advantage of the many different molecules of DNA to try many different possibilities at once. For certain specialized problems, DNA computers are faster and smaller than any other computer built so far. But DNA computing does not provide any new capabilities from the standpoint of Computational_complexity_theory, the study of which computational problems are difficult. For example, problems which grow exponentially with the size of the problem (EXPSPACE problems) on Von_Neumann_machines still grow exponentially with the size of the problem on DNA machines. For very large EXPSPACE problems, the amount of DNA required is too large to be practical. (Quantum_computing, on the other hand, ''does'' provide some interesting new capabilities). ==References== *{{cite journal | author = Leonard M. Adleman | date = 2004-11-11 | title = Molecular Computation Of Solutions To Combinatorial Problems | journal = Science_(journal) | volume = 266 | issue = 11 | pages = 1021–1024 | url = http://www.usc.edu/dept/molecular-science/papers/fp-sci94.pdf }} — The first DNA computing paper. Describes a solution for the directed Hamiltonian_path_problem. *{{cite book | author = Martyn Amos | year = 2005 | month = June | title = Theoretical and Experimental DNA Computation | publisher = Springer | id = ISBN 3-540-65773-8 | url = http://www.springeronline.com/sgw/cda/frontpage/0,11855,3-0-22-1995351-0,00.html }} — The first general text to cover the whole field. *{{cite journal | author = Dan Boneh, Christopher Dunworth, Richard J. Lipton, and Jiri Sgall | year = 1996 | title = On the Computational Power of DNA | journal = DAMATH: Discrete Applied Mathematics and Combinatorial Operations Research and Computer Science | volume = 71 | url = http://citeseer.ist.psu.edu/boneh95computational.html }} — Describes a solution for the Boolean_satisfiability_problem. *{{cite book | author = Gheorge Paun, Grzegorz Rozenberg, Arto Salomaa | year = 1998 | month = October | title = DNA Computing - New Computing Paradigms | publisher = Springer-Verlag | id = ISBN 3540641963 }} — The book starts with an introduction to DNA-related matters, the basics of biochemistry and language and computation theory, and progresses to the advanced mathematical theory of DNA computing. *{{cite journal | author = Lila Kari, Greg Gloor, Sheng Yu | year = 2000 | month = January | title = Using DNA to solve the Bounded Post Correspondence Problem | journal = Theoretical Computer Science | volume = 231 | issue = 2 | pages = 192–203 | url = http://citeseer.ist.psu.edu/kari00using.html }} — Describes a solution for the bounded Post_correspondence_problem, a hard-on-average NP-complete problem. * The history of the International Meeting on DNA Computing (Proceedings - Links) -- http://hagi.is.s.u-tokyo.ac.jp/dna/ ==External links== * How Stuff Works explanation * Physics Web * Ars Technica * A Bibliography of Molecular Computation and Splicing Systems * NY Times DNA Computer for detecting Cancer Category:Computer_hardware Category:Molecular_biology De:DNA-Computer Fr:Ordinateur_à_ADN Ja:DNAコンピュータ Tr:DNA_bilgisayarları