🚀 go-pugleaf

From article <105875@netnews.upenn.edu>,
by barkdoll@lepomis.psych.upenn.edu (spacesareforthefeebleminded):
> In article <1759@tdat.teradata.COM> swf@tools3teradata.com
> (Stan Friesen) writes:
>>In article <104941@netnews.upenn.edu>,
>>rowe@pender.ee.upenn.edu (Mickey Rowe) writes:

>>|> >The brain statement is based on the fact that neurons have less
>>|> >DNA per unit weight than other kinds of cells (eggs-cluding eggs
>>|> >and who knows what other special cases).  

>>|> I suspect that this is generally untrue.

>>Ah, but it is in fact exactly literally true!  All cells in a single
>>body have the *same* amount of DNA (with a few wierd exception like
>>the polytene chromosomes in the salivary glands of Drosophila).

> 	Ah, but it is in fact exactly literally false!  Class
> switching of B cells, antigen specificity selection of immunoglobulins
> and T cell receptor specifity all involve deletion and recombination
> of DNA.  Then of course most ("most" is just to hedge my bets) mature
> mammalian red blood cells have NO nuclear DNA.

First of all, I would argue that both your examples might be classified
as "weird exceptions".  More importantly, I am skeptical that the
DNA rearrangements you refer to could have any measureable effect on
the rather crude DNA-per-unit-weight measurement.

--

Steve Matheson   Program in Neuroscience   University of Arizona
sfm@neurobio.arizona.edu