Patch oligodeoxynucleotide synthesis (POS): a novel method for synthesis of long DNA sequences and full-length genes.

Synthesis of long DNA fragments is often associated with mutations and requires multiple DNA manipulation steps. A novel DNA synthesis method, referred to as patch oligodeoxynucleotide synthesis (POS) to assembly long DNA fragments is presented here. This method involves connection of two types of oligodeoxynucleotides: long constructional oligonucleotides (COs) and short patch oligonucleotides (POs). Long COs were connected by a ligase with the aid of POs, which were complementary to both adjacent COs to help remove secondary structures during assembly. The partial double-stranded DNA template that was formed was then amplified by PCR. Accordingly, we synthesized SV40 polyadenylation signal sequences (187 bp), a codon-optimized yellow fluorescent protein gene (678 bp), and Rattus norvegicus catenin β1 (2,352 bp). This presented method can be broadly applied to synthesize DNA fragments of varying lengths with great convenience.