Nucleotide sequences found in the structural genes of eukaryotes that are non-coding and interrupt the sequences containing information that codes for polypeptide chains. Intron sequences are spliced out of their RNA transcripts before maturation and protein synthesis. (cf. Exons)
DNA sequences that interrupt the protein-coding sequences of a gene (exons) and are eventually spliced out. Only the exons are translated into protein. The function of introns is still being explored.
Noncoding DNA sequences that interrupt the sequences containing instructions for making a protein (exons). Introns are not represented in messenger RNA; only the exons are translated into protein. The function of introns is still being explored.