Double helix
hideIn geometry a double helix (plural helices) typically consists of two congruent helices with the same axis, differing by a translation along the axis, which may or may not be half-way.
The term "double helix" is commonly encountered in molecular biology, where it refers to the structure of DNA. The double-helix model of DNA structure was first published in the journal Nature by James D. Watson and Francis Crick in 1953, based upon the crucial X-ray diffraction image of DNA (labeled as "Photo 51") from Rosalind Franklin in 1952 , followed by her more clarified DNA image with Raymond Gosling, Maurice Wilkins, Alexander Stokes and Herbert Wilson, as well as base-pairing chemical and biochemical information by Erwin Chargaff.
Crick, Wilkins and Watson each received one third of the 1962 Nobel Prize in Physiology or Medicine for their contributions to the discovery. (Franklin, whose breakthrough X-ray diffraction data was used to formulate the DNA structure, died in 1958, and thus was ineligible to be nominated for a Nobel Prize.)
The DNA double helix is a right-handed spiral polymer of nucleic acids, held together by nucleotides which base pair together. A single turn of the helix constitutes ten nucleotides. The double helix structure of DNA contains a major groove and minor groove, the major groove being wider than the minor groove. Given the difference in widths of the major groove and minor groove, many proteins which bind to DNA do so through the wider major groove .
The order, or sequence, of the nucleotides in the double helix within a gene specifies the primary structure of a protein.
The term entered popular culture with the publication in 1968 of The Double Helix: A Personal Account of the Discovery of the Structure of DNA, by James Watson.
For more information about Double helix, read the full article at
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News tagged with double helix
Chemists see first building blocks to life on Earth
May 13, 2009 |
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Scientists at The University of Manchester have developed an experiment that sheds new and fascinating light on how life on Earth might have begun.
Scientists decipher the 3-D structure of the human genome
Oct 08, 2009 |
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(PhysOrg.com) -- Scientists have deciphered the three-dimensional structure of the human genome, paving the way for new insights into genomic function and expanding our understanding of how cellular DNA folds ...
Backtracking on DNA
Jun 23, 2009 |
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(PhysOrg.com) -- Accuracy is essential for life, so in converting the information stored in DNA into a form in which it can be used, a high level of precision is required. Dr Tanniemola Liverpool from the ...
New nucleotide could revolutionize epigenetics
Apr 16, 2009 |
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Anyone who studied a little genetics in high school has heard of adenine, thymine, guanine and cytosine - the A,T,G and C that make up the DNA code. But those are not the whole story. The rise of epigenetics in the past decade ...
Chemists Reach from the Molecular to the Real World with Creation of 3-D DNA Crystals
Sep 02, 2009 |
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(PhysOrg.com) -- New York University chemists have created three-dimensional DNA structures, a breakthrough bridging the molecular world to the world where we live. The work, reported in the latest issue of ...
Gene transcribing machine takes halting, backsliding trip along the DNA
Jul 30, 2009 |
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(PhysOrg.com) -- The body's nanomachines that read our genes don't run as smoothly as previously thought, according to a new study by University of California, Berkeley, scientists.
Build your own space station
Space & Earth / Space Exploration
Mar 03, 2009 |
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(PhysOrg.com) -- CSIRO's Double Helix Science Club has produced a paper model of the International Space Station (ISS) - the first designed just for children.
Biologists discover link between CGG repeats in DNA and neurological disorders
Biology /
Jan 11, 2009 |
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Researchers have long known that some repetitive DNA sequences can make human chromosomes "fragile," i.e. appearing constricted or even broken during cell divisions. Scientists at Tufts University have found that one such ...
Chemists create bipedal, autonomous DNA walker
Apr 02, 2009 |
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Chemists at New York University and Harvard University have created a bipedal, autonomous DNA "walker" that can mimic a cell's transportation system. The device, which marks a step toward more complex synthetic molecular ...
Researchers explain process by which cells 'hide' potentially dangerous DNA segments
Apr 09, 2009 |
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The DNA in the 23 pairs of chromosomes in each of the billions of cells of the human body is so tightly packed that it would measure six feet in length if stretched end to end. A genome of this size can squeeze into a cell's ...
Scientists find shared genetic link between periodontitis and heart attack
May 25, 2009 |
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The relationship between the dental disease periodontitis and coronary heart disease (CHD) has been known for several years. Although a genetic link seemed likely, until now its existence was uncertain. Now, for the first ...
Professor sheds light on DNA mechanisms
Jul 17, 2009 |
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By manipulating individual atoms in DNA and forming unique molecules, a Georgia State University researcher hopes to open new avenues in research towards better understanding the mechanisms of DNA replication and transcription, ...
Discovery may result in new test to determine predisposition to cancer
Mar 25, 2009 |
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Researchers at UCLA's Jonsson Comprehensive Cancer Center have developed an assay that may be used to help identify new genes that can predict a predisposition to cancer.
Researchers unravel mystery of DNA conformation
Jul 13, 2009 |
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An iconic photograph (http://img.timeinc.net/time/80days/images/530228.jpg) of Nobel laureates Drs. Francis Crick and James Watson show the pair discussing with a rigid model of the famous double helix. ...
Models begin to unravel how single DNA strands combine
Nanotechnology / Bio & Medicine
Oct 05, 2009 |
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(PhysOrg.com) -- Using computer simulations, a team of University of Wisconsin-Madison researchers has identified some of the pathways through which single complementary strands of DNA interact and combine to form the double ...
