Introns are regions of DNA which are non-coding. They do not form part of the mature mRNA product and are spliced out during protein synthesis. This is done by an enzyme consisting of both proteins and RNA called the spliceosome. Introns are only found in eukaryotic genes . They should not be confused with exons, which are the coding regions of DNA sequences.
- ↑ Alberts et al. (2008) Molecular Biology Of The Cell, 5th edition, New York: Garland Science.