Patent ID: 8026050

Claim:
A method of modifying a polynucleotide, said method comprising: (a) providing in combination: i) a first oligonucleotide or a molar excess of said first oligonucleotide relative to the concentration of said polynucleotide, with said first oligonucleotide having a 3′ portion capable of reversibly hybridizing to said polynucleotide and a 5′ portion which does not hybridize to said polynucleotide, and ii) a 5′-nuclease, and (b) reversibly hybridizing under isothermal conditions said polynucleotide and said first oligonucleotide, wherein said first oligonucleotide, when hybridized to said polynucleotide, is cleaved by said 5′-nuclease as a result of the presence of said polynucleotide to provide: (i) a first fragment that is substantially non-hybridizable to said polynucleotide, or a first fragment including said 5′ portion and no more than one nucleotide from the 5′ end of said 3′ portion, and (ii) a second fragment that is 3′ of said first fragment with reference to said first oligonucleotide and is substantially hybridizable to said polynucleotide, thereby modifying said polynucleotide.