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Pronunciation: an-nēl′


  1. To soften or temper a metal by controlled heating and cooling; the process makes a metal more easily adapted, bent, or swaged, and often less brittle.
  2. In dentistry, to heat gold leaf preparatory to its insertion into a cavity, to remove adsorbed gases and other contaminants.
  3. The pairing of complementary single strands of DNA; or of DNA-RNA.
  4. The attachment of the ends of two macromolecules, two microtubules annealing to form one longer microtubule.
  5. In molecular biology, annealing is a process in which short sections of single-stranded DNA from one source are bound to a filter and incubated with single-stranded, radioactively conjugated DNA from a second source. Where the two sets of DNA possess complementary sequences of nucleotides, bonding occurs. The degree of relatedness (homology) of the two sets of DNA is then estimated according to the radioactivity level of the filter. This technique plays a central role in the classification of bacteria and viruses.
  6. To renature proteins or polynucleic acids by slow cooling.

Synonym(s): nucleic acid hybridization

[A.S. anaelan, to burn]

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© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.