Process for the in vivo recombination of DNA sequences having mismatched bases

Claim 1

A process for producing a hybrid organism, comprising: combining in a cell or cells of an organism a double-stranded DNA from a first species or genus with a double stranded DNA from a second species or genus, said first and second DNAs having sequences which are partially homologous and have mismatches able to activate the enzymatic mismatch repair system of the cell when said system is functional, wherein the enzymatic mismatch repair system is defective or has been inactivated transitorily to enable stable recombination between said DNA sequences, wherein said process is selected from the group of processes consisting of: (i) fusing cells of an organism of a first species or a first genus with cells of an organism of a second species or a second genus, said cells of said organism of a second species or a second genus having a defective enzymatic mismatch repair system or having said system inactivated transitorily; (ii) crossing a unicellular organism of a first species or a first genus with a unicellular organism of a second species or a second genus, wherein at least one organism has a defective enzymatic mismatch repair system or has said system inactivated transitorily; (iii) conjugating or transducing a recipient bacterium of a first species or a first genus and a donor bacterium of a second species or a second genus, said donor bacterium having at least one DNA sequence to be transferred to said recipient bacterium, wherein at least one of said donor bacterium and said recipient bacterium includes a defective enzymatic mismatch repair system or said system is inactivated transitorily; (iv) inactivating said enzymatic mismatch repair system by at least one mutation of at least one of the mutS and mutL genes; and (v) placing into a unicellular organism defective or inactivated in the enzymatic mismatch repair system two DNA sequences, said two DNA sequences being partially homologous genes derived from two different organisms, and selecting the desired hybrid sequence, gene, or product thereof, and selecting said cell or cells of said organism containing said recombined DNA.