question about evolution theory

Bob Rutledge brutledge at pnfi.forestry.ca
Wed Apr 27 21:05:42 EST 1994


In article <lawrence-180494131124 at ls-12.biology.utah.edu> lawrence at bioscience
.utah.edu (Jeff Lawrence) writes:
=>stuff deleted
> the job of
>evolutionary biologists is to sort the meaningful patterns from the
>background noise.  this is especially difficult in molecular evolution, as
>one can imagine, in that the ancestry of homologous characters may be
>difficult to ascertain (hard to line up sequences to identify base position
>that are identical by descent), and there are only four character states
>(G,A,T,C).  Despite these difficulties, molecular changes can be sorted out
>to identify gene families and trace their lineages (for example, globin
>genes among mammals or transposase genes among Eukarya and Bacteria).

>jeff

I would like to point out that indels (insertions and deletions) are another 
important "character state" that could be utilized for investigating the 
evolutionary ancestry of genes.  Although I have not seen much literature 
referring to the utility of indels for evolutionary studies, its clear that 
they could provide an important "marker" of ancestry, in that they are not as 
frequently/easily reversible as are single base pair changes.   In particular, 
when they occur within a region that encodes a highly conserved peptide, such 
rare events provide markers that could survive for extensive evolutionary 
periods.  Our work on MADS box genes of spruce has reveal one potential
indel within the highly conserved DNA binding region, that maybe 
representative of this.  If there is any interest in this aspect of molecular 
evolution, I would be happy to provide additional information about this gene 
segment.

Bob




More information about the Mol-evol mailing list