No bands in RFLP - (Feb/07/2007 )
Hi,
Iam currently doing an RFLP with BbvI (NEB). I first perform a PCR followedd by RFLP .
My PCR gives sharp band,but when it is used in RFLP,and then loaded in gel,there is no band,not even the one seen in PCR.
These are my reaction conditions,
water-34ul,DNA-7ul,Buffer5ul(10X NE buffer2) and 8unit BbvI
kindly help..
You could have DNAsa contamination or your agarosa gel is not stained properly.
I don’t know what is your PCR product size and how many fragments you are expecting. May be your amount of PCR product is enough to see it but the amount of your fragments are not. 
Did you repeated? May be you forgot to add the DNA or you add an smaller amount.
Are your gel running properly? some times the gel up a little just by a side because of the bubbles and DNA goes out (it has happened to me a few times). 
I don’t know what is your PCR product size and how many fragments you are expecting. May be your amount of PCR product is enough to see it but the amount of your fragments are not.
Did you repeated? May be you forgot to add the DNA or you add an smaller amount.
Are your gel running properly? some times the gel up a little just by a side because of the bubbles and DNA goes out (it has happened to me a few times).
Another possibility is that the enzyme cutted your fragment to too small pieces, that ran out of the gel or are not visible anymore. Do you know the sequence of the fragment? If so try out larger amount of DNA for better visible small fragments (if this is the problem) or use a higher percentage gel.