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Name: Daulat
Status: Other
Grade:  Other
Location: N/A
Country: N/A
Date: January 2007

When we say intron, does it represent sequence of RNA that is cut off during RNA splicing or sequence of DNA that after transcription are cut off during RNA splicing?

The word intron refers to a DNA sequence whose transcript will be spliced out during mRNA processing.

C. Perkins

Either. It is the sequence of DNA/RNA that is not found in the final processed RNA. You can search for intronic sequences in DNA for example. If you know the final translation of the protein you can compare the number of bases in DNA to the number of amino acids in the protein and if there were no introns, the DNA should be exactly 3 times the length of the protein chain. But it isn't. So the DNA contains extra letters that don't make it into the protein and represent the introns in the DNA.


Intron refers to the region of a gene (DNA) that does not code for the amino acid sequence of the corresponding protein. It is the template for the synthesis of the region of mRNA that will spliced out during mRNA processing.

Ron Baker, Ph.D.

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