Stephen Wray Steve.Wray at comp.vuw.ac.nz
Thu Jun 20 02:00:07 EST 1996

>>>>> "Mary" == Mary K Kuhner <mkkuhner at phylo.genetics.washington.edu> writes:

 Mary> In article <4q9fn7$p4k at bolivia.it.earthlink.net> MIKE  LAMB <mikejonlamb at earthlink.net> writes:
 >> Here is one intron benefit: Cancer prevention aid.  Introns can take 
 >> hits from chemical carcinogens. These hits might otherwise hit and 
 >> mutate an exon causing more damage. The more introns there are, the 
 >> fewer damaging mutations occur. 

 Mary> But non-transcribed spacers between genes would seem to accomplish the
 Mary> same effect with much less cost to the cell.  Synthesizing mRNA
 Mary> corresponding to an intron, cutting it out, and throwing it away is a
 Mary> mildly expensive operation, and it would seem advantageous to replace it
 Mary> with something simpler.

I've wondered about the cost to the cell of introns -- what happens to the intron
strand once it is spliced out? Is it used for *anything* in cell metabolism?

 Mary> Hits to introns can also be deleterious, if they disrupt the splicing
 Mary> signals--it seems quite easy to silence or botch a gene by preventing it
 Mary> from splicing correctly.

It might cause it to be expressed... Also, introns may play a role in the folding
of chromosomes -- they arn't scrunched up randomly...

I used to think that my brain was the most wonderful organ in my body.

Then I realised who had been telling me this...

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