US Patent 7534569 Method of generating long nucleic acid molecules of defined sequence

A method of generating a single-stranded nucleic acid molecule comprising (a) combining in a mixture under conditions suitable for a polymerase extension reaction, (i) a polymerase, (ii) an initial polynucleotide comprising a 5′ portion and a 3′ portion, wherein the polynucleotide forms the nucleic acid molecule 5′ end; and (iii) a plurality of overlapping template oligonucleotides each having a 5′ template portion and a 3′ portion. The method further comprises (b) hybridizing the initial polynucleotide or the extension polynucleotide and one of the template oligonucleotides; (c) incubating the mixture for sufficient time to allow an extension polynucleotide to be synthesized; (d) adding a competimer that competes with the template oligonucleotide in step (b); (e) denaturing the extension polynucleotide and template oligonucleotide; and (f) repeating steps (b), (c), (d), and (e) to generate the single-stranded nucleic acid molecule, wherein the number of repeated cycles equals the number of different template oligonucleotides.