Gene synthesis: methods and applications

DNA synthesis techniques and technologies are quickly becoming a cornerstone of modern molecular biology and play a pivotal role in the field of synthetic biology. The ability to synthesize whole genes, novel genetic pathways, and even entire genomes is no longer the dream it was 30 years ago. Using little more than a thermocycler, commercially synthesized oligonucleotides, and DNA polymerases, a standard molecular biology laboratory can synthesize several kilobase pairs of synthetic DNA in a week using existing techniques. Herein, we review the techniques used in the generation of synthetic DNA, from the chemical synthesis of oligonucleotides to their assembly into long, custom sequences. Software and websites to facilitate the execution of these approaches are explored, and applications of DNA synthesis techniques to gene expression and synthetic biology are discussed. Finally, an example of automated gene synthesis from our own laboratory is provided.