Newsgroups: sci.bio
Path: utzoo!utgpu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!alchemy.chem.utoronto.ca!mroussel
From: mroussel@alchemy.chem.utoronto.ca (Marc Roussel)
Subject: Re: Reconstructing cells from DNA
Message-ID: <1991Apr14.211248.2072@alchemy.chem.utoronto.ca>
Organization: Department of Chemistry, University of Toronto
References: <18637@csli.Stanford.EDU> <1991Apr13.203239.22379@hollie.rdg.dec.com>
Date: Sun, 14 Apr 1991 21:12:48 GMT

In article <1991Apr13.203239.22379@hollie.rdg.dec.com>
winalski@psw.enet.dec.com (Paul S. Winalski) writes:
>I don't think that there are any cases of non-nucleic-acid-based hereditary
>mechanisms in any known organisms.  Such mechanisms might be possible, but
>living organisms don't make use of them.

     I don't think that right, unless you want to extend the meaning of
"hereditary mechanisms" to the point of meaninglessness.  Most
biological morphogenesis in multi-celled organisms is now known to be
the result of complex spatio-temporal interactions (chemical waves and the like)
between embryo gene products and the chemical environment provided by
the egg and/or uterus.  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.)

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