GC melt

[R. John Lye]

ssands at my-deja.com wrote:
> 
> In the article from The Scientist the author says
> that one should not put a string of G or C bases at
> the 3' end of a PCR primer because they could cause
> nonspecific amplification products.  I had heard
> that I _should_ do this to get a GC-clamp.
> 
> Does anyone have any insight into this apparent
> conflict?

Well, Debra Swanson suggests avoiding *three* G's or
C's at the 3' end of the primer.  I aim for *two* G's
or C's to get a GC clamp, so there's no conflict
with her advice that I see.  It all depends on the
length of the clamp.  That said, I've used a three 
base long clamp on ocassion without problems.

-- 
John Lye

e-mail to: rjl6n at Virginia.EDU
homepage: http://avery.med.virginia.edu/~rjl6n/homepage.htm