Patent ID: 8455190

Claim:
A method for enriching a target nucleic acid sequence in a reaction mixture, said method comprising: a. subjecting a reaction mixture suspected of having a target sequence duplex and a reference sequence duplex to a first denaturing temperature that is above the melting temperature (T m ) of the target sequence duplex and the reference sequence duplex so as to permit the denaturation of said target sequence duplex and said reference sequence duplex to form target strands and reference strands, wherein said target sequence duplex comprises one or more insertion, deletion or substitution and differs by at least one nucleotide from said reference sequence duplex and is amplifiable by the same primer pair as said reference sequence duplex; b. reducing the temperature of the reaction mixture so as to permit formation of target strand/reference strand duplexes; c. subjecting said reaction mixture to a critical temperature (T c ) that is below the T m of said reference sequence duplex so as to permit the preferential denaturation of said duplex of step (b) to form denatured target and reference strands; d. reducing the temperature of the reaction mixture so as to permit said primer pair to anneal to said target and reference strands; and e. extending said primer pair so as to enrich said target sequence relative to said reference sequence.