An IPCR Tale

[SPAGNOL at PLAUTO.CSATA.IT]

Dear colleagues,
here is the story of my IPCR:

First try: (1.5 mM MgCl2): smear

Second try: (MgCl2 optimized to 4.5 mM): smear, plus 
very,very faint band at 600 bp.

Third try: ( Annealing T brought from 52 C to 60 C): 
smear, plus faint band at 600 bp

Fourth try: ( using the "stick in the toothpick" method 
to isolate the 600 bp band ): VERY CLEAR band at 600 bp. Still the 
smear, even if much fainter, is still there.

Question: should I ignore the smear, go ahead and subclone the 
product, or try to get rid of it? And how?.Thanks.Giorgio.