Patent ID: 6506603
Filing Date: 2003-01-14
Classification: C07K,C12N,C12Q,C12Y,C40B,Y10S

Abstract:
A method for producing a variant polynucleotide, comprising:(a) conducting a polynucleotide extension process under conditions resulting in incomplete extension of synthesized polynucleotides to produce a plurality of polynucleotides in various stages of synthesis; wherein incomplete extension is achieved by either (1) a shortened extension time relative to the time required for complete extension of the synthesized polynucleotides, or (2) addition of an agent selected from the group consisting of a chemical mutagen, an intercalating agent, irradiation, a polymerase, a nucleotide analogs, and recA; (b) denaturing the plurality of polynucleotides; (c) incubating the denatured plurality of polynucleotides with a polymerase under conditions which result in annealing of single-stranded polynucleotides at regions of complementarity between the single stranded polynucleotides and formation of variant double stranded polynucleotide chains; (d) repeating (b) and (c); (e) screening or selecting a plurality of variant polynucleotides or expression products thereof and thereby identifying a variant polynucleotide having a useful functional activity.