n. (label en genetics) A segment of DNA that is part of the genome of an organism, and which is similar to a gene but does not code for a gene product.
Pseudogenes are functionless relatives of genes that have lost their gene expression in the cell or their ability to code protein. Pseudogenes often result from the accumulation of multiple mutations within a gene whose product is not required for the survival of the organism. Although not protein-coding, the DNA of pseudogenes may be functional, similar to other kinds of noncoding DNA which can have a regulatory role.
Although some pseudogenes do not have introns or a promoter (these pseudogenes are copied from messenger RNA and incorporated into the chromosome and are called processed pseudogenes), most have some gene-like features such as promoters, CpG islands, and splice sites. They are different from normal genes due to a lack of protein-coding ability resulting from a variety of disabling mutations (e.g. premature stop codons or frameshifts), a lack of transcription, or their inability to encode RNA (such as with ribosomal RNA pseudogenes). The term was coined in 1977 by Jacq et al.
Because pseudogenes are generally thought of as the last stop for genomic material that is to be removed from the genome, they are often labeled as junk DNA. A pseudogene can be operationally defined as a fragment of nucleotide sequence that resembles a known protein's domains but with stop codons or frameshifts mid-domain. Nonetheless, pseudogenes contain biological and evolutionary histories within their sequences. This is due to a pseudogene's shared ancestry with a functional gene: in the same way that Darwin thought of two species as possibly having a shared common ancestry followed by millions of years of evolutionary divergence, a pseudogene and its associated functional gene also share a common ancestor and have diverged as separate genetic entities over millions of years.
Pseudogene is a database of pseudogenes annotations compiled from various sources.
Usage examples of "pseudogene".
The rats had borne a few, early on, before the pseudogene structure was fine-tuned.
Moss Frantz swiped thousands of units of the pseudogene factor, and tried to take them outside the Enclave.
Moss felt no need to mention that the confiscated batch of oral-effective pseudogene was only one of two, nor that the second was safely stowed for later distribution.
So the Foundation kept its experiments with the pseudogene strictly in-house, using only volunteers and maintaining secrecy while watching for possible side effects.
I want this pseudogene thing made available throughout this country and to any other nation that wants it.
We thought it would require two separate designs of pseudogenes, to slip X and Y chromosomes past ovum-immunity.
Most of it is satellite repeat sequences, but in between the satellites there are hundreds of thousands of truncated genes and pseudogenes, all of them in a constant state of crossgenerational flux because of transposon activity.