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From: rowe@pender.ee.upenn.edu (Mickey Rowe)
Newsgroups: sci.bio
Subject: Re: Reconstructing cells from DNA
Message-ID: <41171@netnews.upenn.edu>
Date: 15 Apr 91 04:07:49 GMT
References: <18637@csli.Stanford.EDU> <1991Apr13.203239.22379@hollie.rdg.dec.com> <1991Apr14.211248.2072@alchemy.chem.utoronto.ca>
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In article <1991Apr14.211248.2072@alchemy.chem.utoronto.ca> mroussel@alchemy.chem.utoronto.ca (Marc Roussel) writes:

>  The number of digits that a person (or other 
>mammal) develops is now known to be determined by chemical waves at
>certain stages of development rather than by direct coding.  (I'm afraid
>that I can't produce any references at the moment due to a library
>strike at the University of Toronto.)

How well is this known?  I'm aware of the affects that retinoic acid
has on developing and regenerating limbs, and I know that most
developmental biologists anticipate that we will find morphogens that
orchestrate such development in situ, but I think your statement might
be a little strong.  I'm only dimly aware of it, but there seems to be
a storm brewing about retinoic acid, and it seems most people are
backing away from the position that it does what you say.  Is there
perhaps something else that you had in mind?  If there is or if my
understanding is inaccurate, I'd love to hear about it.

>				Marc R. Roussel
>                                mroussel@alchemy.chem.utoronto.ca

Mickey Rowe     (rowe@pender.ee.upenn.edu)