Calculating Tm for mismatch on Northern

Mark D. Garfinkel mg16 at
Thu Jul 27 10:42:28 EST 1995

In article <1995Jul24.133759.8909 at mbcf>,  <neale at> wrote:
>We have a partial cDNA clone from mouse that we wish to screen *human* northern
>My question is whether you can calculate a lower stringency and wash of these
>blots the same as you would for Southerns?
	Same formula, different effective Tm. It's the difference between
	detecting DNA-DNA hybrids and DNA-RNA hybrids, the latter being
	more stable, and the differential effects thereon caused by
	formamide-containing hybridization solutions. See, for example,
	White & Davis (1976) PNAS and Casey & Davidson (1977) NAR for the
	original experiments.

Mark D. Garfinkel (e-mail: mg16 at
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