pseudogene
Sign in to savealt=Drawing of a gene showing kinds of defects (missing promoter, start codon or introns, premature stop codon, frameshift mutation, partial deletion).|540x540px|thumb Pseudogenes are nonfunctional segments of DNA that resemble functional genes. Pseudogenes can be formed from both protein-coding genes and non-coding genes. In the case of protein-coding genes, most pseudogenes arise as superfluous copies of functional genes, either directly by gene duplication or indirectly by reverse transcription of an mRNA transcript. Pseudogenes are usually identified when genome sequence analysis finds gen
Article
15 sectionsContents
- Properties
- Types and origin
- Processed
- Non-processed (duplicated)
- Unitary pseudogenes
- Polymorphic pseudogenes
- Transcribed but non-functional pseudogenes
- Examples of pseudogene function
- Protein-coding: "{{vanchor|pseudo-pseudogenes}}"
- Non-protein-coding
- Bacterial pseudogenes
- See also
- References
- Further reading
- External links
alt=Drawing of a gene showing kinds of defects (missing promoter, start codon or introns, premature stop codon, frameshift mutation, partial deletion).|540x540px|thumb Pseudogenes are nonfunctional segments of DNA that resemble functional genes. Pseudogenes can be formed from both protein-coding genes and non-coding genes. In the case of protein-coding genes, most pseudogenes arise as superfluous copies of functional genes, either directly by gene duplication or indirectly by reverse transcription of an mRNA transcript. Pseudogenes are usually identified when genome sequence analysis finds gene-like sequences that lack regulatory sequences or are incapable of producing a functional product. Pseudogenes are a type of junk DNA.
Most non-bacterial genomes contain many pseudogenes, often as many as functional genes. This is not surprising, since various biological processes are expected to accidentally create pseudogenes, and there are no specialized mechanisms to remove them from genomes. Eventually pseudogenes may be deleted from their genomes by chance of DNA replication or DNA repair errors, or they may accumulate so many mutational changes that they are no longer recognizable as former genes. Analysis of these degeneration events helps clarify the effects of non-selective processes in genomes.