From owner-diagnostics@net.bio.net Thu Mar 23 22:00:00 1995 Path: biosci!PLAINS.NODAK.EDU!dwatson From: dwatson@PLAINS.NODAK.EDU (David Watson) Newsgroups: bionet.diagnostics Subject: High-altitude PCR Date: 24 Mar 1995 08:21:16 -0800 Organization: BIOSCI International Newsgroups for Molecular Biology Lines: 12 Sender: daemon@net.bio.net Distribution: world Message-ID: <199503241620.AA10807@plains.NoDak.edu> NNTP-Posting-Host: net.bio.net One more bit re: the PCR question. Tm's for most DNA's of approx. 40 % G+C are 85-90 C (in, e.g. TE buffer), such that with even 40-50% of the template melted, it might still be possible to routinely amplify targets by melting at say 88 C. I think David Juck makes a good point when he says that subsequent denaturation of the much smaller amplicon could be much easier (but only if it doesn't have a high G+C content). Before adding DMSO or glycerol or whatever, I'd be inclined to just give it one shot at 88 C. You might accomplish your objective without further fine-tuning. There might also be the added benefit of less temperature-related damage to the DNA. Dave Watson .