DNA Recombination\duplication assay

[cwh at staff.monash.edu.au]

Hi people
I am trying to design a recombination assay of some sort to detect duplication 
of a large region of DNA in a bacteria.  I have a few putative recombinases 
cloned and am hoping to overexpress them in a background that will select for 
duplication (presumably using a marker gene of some kind).  It sounded easy 
but is harder in practice than in theory.  Any help would be greatly 
appreciated

chris