reading frame

(redirected from open reading frame (ORF))
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read·ing frame

(rēd'ing frām),
The grouping of nucleotides by threes into codons. See: frameshift mutation.

reading frame

n.
One of the three possible ways in which an mRNA sequence of nucleotides can be read as a series of base triplets to specify the amino acids in a protein chain.

reading frame

An imaginary window through which base pairs can be inspected three at a time, and which provides a way in which a nucleotide sequence can be viewed as three different sets of CODONs only one of which is correct.

reading frame

the actual codons that are translated (read) during mRNA synthesis. In principle a DNA sequence can be transcribed in any one of three different reading frames, each of which will specify a completely different polypeptide. Usually only one of the three reading frames is transcribed.

open reading frame (ORF)
an extended sequence in mRNA that is free of stop codons.