In article <432cog$kcq at news.cc.utah.edu>,
David Witherspoon <dwithers at genetics.utah.edu> wrote:
> I am studying a family of transposable elements (TBE1s) in a
>couple of species of ciliates (Oxytricha fallax and trifallax.) These
>are
>DNA "Cut and Paste" transposons. The most striking feature of this
>family is the degree of conservation between elements: virtually all of
>the several thousand elements in any given host genome are intact,
>meaning that no stop codons, no deletions or insertions, and few
>nonsynonymous changes (relative to synonymous changes) have
>occurred during their divergence from each other. I take this to be
>evidence that some force of purifying selection has been acting on these
>elements over a long period within the host population.
Could it be that these two species have only recenly arisen from a common
ancestor, and thus have not had time to change their genome? About the
lack of mutations, is there no exons in the genome? Those would tend to
mutate more I would think...
-Rob
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Robert Dejournett hermes at rtd.comhttp://www.rtd.com/~hermes
"For the greatest good, for the largest number, for the longest time" G Pichot
