Detection of punctual mutations

[COLINE at rulsfb.LeidenUniv.nl]

Are you sure it(PGGE) can not detect mutations A to T, T to A, G to C and
C to G. We are going to set it up in our lab with the idea that it can detect
these mutations. Because I thought it does not only depend on the nucleotide
but also on the surrounding nucleotides, since the sequence changes it 
gives another band. But I never checked for proof. 
Does anybody have evidence for this?

Coline