There are/were also `orphan' genes which used to mean duplicated genes
that inactivated due to mutation. These were distinguished from
pseudogenes which were supposed to be intron-less copies of processed
RNAs. The terminology has become less delimited and my perception is
that `pseudogene' has come to mean any non-coding sequence related by
homology (by descent) to a coding sequence.
> To: molecular-evolution at net.bio.net> From: robison at mito.harvard.edu (Keith Robison)
> Subject: Re: Pseudogenes
> Date: 9 Sep 1995 14:50:25 GMT
> Ram Samudrala (ram at mbisgi.umd.edu) wrote:
> : Paul Linehan (linehan at ceph.cephb.fr) wrote:
>> : >They can of course be ancient or recent. They normally arise from
> : >functional genes and not vice-versa (at least to my knowledge).
>> : If a functional gene arose from a pseudogene, it would not be
> : classified as a pseudogene.
>> It's not clear that this is true -- a pseudogene (or portions
> of it) might be resurrected -- much in the way a wrecked car
> can still provide useful parts. A pseudogene which has undergone
> only a few mutational hits might be resurrected in part by
> combining with another gene.
>> There is a related concept in microbiology of a "cryptic gene"
> -- an inactive gene which can be reactivated by mutation.
>>> Keith Robison
> Harvard University
> Department of Cellular and Developmental Biology
> Department of Genetics / HHMI
>>robison at mito.harvard.edu>>>>>//========================================================\\
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