Annealing temperature for oligos

[Thomas Urbig]

Adela.Torres at uv.es (Adela Torres Calatayud) wrote:
>Hi everybody:
>
>I'm currently working on DNA non-radioactive cycle sequencing, and I'd like to 
>know if there is a reliable formula by which I can choose the annealing 
>temperature of the PCR program when I'm sequencing using custom-made oligos. 
>Right now the formula I'm using is:
>
>		2(A+T) + 4(G+C) - 6 = T ann.
>
>But it didn't give me good results when I tried it. So if there's anyone out 
>there that can help me, thanks very much! E-mail or post.
>
>					Adela Torres
>				         (Adela.Torres at uv.es)

I don't where you got the formula, the one I am using Is 

Tm = 4(G+C) + 2(A+T)

Ref.: Thein and Wallace 1986, Human Genetic Deseases: A practical approach, K. E. Davis, ed., IRL Press

Hope that helps

                Thomas