From: Jack Correia <jcorreia@fiona.umsmed.edu>
  To  : rasmb@bbri.eri.harvard.edu
  Date: Sat, 13 May 95 14:39:33 -0500

Re: sedimentation database

        A sequence of DNA is of course a derived list of bases [not the raw 
data] that, if authentic and accurate, has some value for comparisons and 
predictions along with a larger data base.  [At least that is what the human 
genome people would have us believe.]  If I measure the molecular weight of 
a protein under a certain set of conditions, how is the raw data of value to 
anyone, except as a means of testing software analysis routines?  It is not 
as if, like a sequence, a protein always gives the same answer.  Depending 
upon conditions, handling, mishandling, aging, purity, etc., one could 
easily get different results.  I recently measured the molecular weight of a 
double stranded piece of DNA, 214 base pairs, and got the "right" answer, if 
we used the "right" vbar, to within 1%.  The person I did it for had a 
reason to test it, but what is the value of the data to others?

        A previous suggestion on this server, by Greg Ralston I think, was 
for data to be deposited for comparitive development of analysis methods.  
Well characterized standards that give clear answers could be of value for 
this purpose, although most of us would start with noise perturbed synthetic 
data!  Some of that is done on the RASMB now!   Such a repository would have 
value as a learning tool, possibly in conjunction with a workshop at UCONN 
or in the UK, or possibly as a tutorial based upon such a workshop.  {Sorry 
Tom, Walter, Jeff, I know I'm suggesting work!]  But a global repository of 
data would be of limited interest to me except for the purpose of testing 
methods.  I also suspect that we would not easily agree on a standarized 
method of presentation.  Walt Stafford prefers DCDT, Bo prefers VanHolde 
Weischet, John Philo may prefer Svedberg, some may prefer biospin or the 
omega function, while I prefer everything that makes sense and contributes 
to the story.  

Jack Correia