>The current thinking regarding pseudogenes includes the idea that they
>are genes that have an obvious DNA sequence similarity to other genes
>but are not expressed. This does not necessarily imply "broken". They
>are common in eukaryotes but their functions are oft debated. Possible
>explanations include...
>
>1. Pseudogenes are remnants of evolutionary mistakes (inactivated by
>mutation rather than being eliminated)
>
>2. Pseudogenes are genes that are in the act of evolving (perhaps one
>day to be activated and expressed)
A point here: if pseudogenes are not expressed, they are not likely to
confer a phenotype on which selection can work. Thus, it is not likely that
pseudogenes are in the process of evolving into a new gene.
>3. While not expressed, pseudogenes play an essential role in the
>expression of their normal counterparts.
This is not nearly as well supported by the evidence as is point #1.
>
>These multiple explanations caution us as to how much weight one should
>give to the pseudogene concept when developing one's model. One can
>easily chose one particular explanation from several proposed by
>geneticists as an assumption from which to build a supporting argument.
While there may be alternative ways to explain pseudogenes, they don't all
have equal probability of being the correct answer as I have illustrated above.
__________________________________________________________________________
Steven S. Clark, Ph.D . Phone: 608/263-9137
Associate Professor FAX: 608/263-4226
Dept. of Human Oncology and Email: ssclark@facstaff.wisc.edu
UW Comprehensive Cancer Center
CSC K4-432
600 Highland Ave.
Madison, WI 53792
"It is the glory of God to conceal a matter, but the glory of kings to
search out a matter." Proverbs
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