PCR machines

[J Preiss--Seq Anal]

in response to Cheung C. Yue, re PCR Machine specs:

	I also did some research on a PCR machine purchase.  

Requirements:
1.	= or < 1 degree C/sec ramp time (most important)
2.	sample volume capacity for numbers (RAPD mapping) or cloning
3.	I prefer a cold holding cycle for overnight runs
4.	I prefer machines that heat all sides of the tube (no mineral oil)

	The new Cetus machines are good, but not necessarily best, and 
expensive.
Things I found from experience and that of friends

1.	Nobody I met was happy with the water circulation heat/cool units
		too slow  on ramp times

By the way, slow ramp times seem to radically increase undefined side
reactions, resulting in lots of background and little product.  I have seen
same temp conditions and samples at slow ramp speeds give only smear back-
ground while at fast ramp times, crisp bands with no background.

2.	Do not buy the BiosCycler (a toaster oven type).  The Univerisity 
of California at Davis was engaged in a lawsuit with them last I heard
because of my unfavorable interaction with them, their product (which did
not perform up to written specs), their service people (who refused to 
return our calls) and their billing office (who billed the university 
during a 30 day trial period without my consent and refused to honor 
the written trial period contract).  This is my personal recomendation,
and does not reflect any official endorsement by the University of CA.
It is also, admittedly, biassed by my experience.

In the end, We gave up the hunt and paid for old reliable...The Cetus 
machine.  
		Good luck finding something better

			Dr. Leonard N. Bloksberg
			PreissJ at clvax1.cl.msu.edu
			MI State University, Dept of Biochemistry