Synthesis of Nucleic Acids

Nucleic acid syntheses in a wide variety of forms are required for multiple research activities: in nucleic acids chemistry, chemical biology, molecular biology, synthetic biology, genetics and precision therapeutics. For the chemical synthesis of most oligonucleotides under 100 bases, the solid-phase phosphoramidite approach has dominated the field for four decades and will continue to do so. Hundreds of thousands of custom oligonucleotides are synthesized around the world every day using this approach. The non-templated enzymatic synthesis of oligonucleotides represents a new frontier in this field that may one day allow direct access to even longer oligonucleotides as well as reducing the consumption of organic solvents. The synthesis of longer constructs, including genes and genomes, can be carried out by assembly of oligonucleotides into larger fragments using polymerases and, where appropriate, ligases. Integration of the techniques described in this chapter – writing, copying and editing sequences and combining DNA from natural and synthetic sources – continues to underpin impressive innovation across multiple fields. The synthesis of nucleic acids is being pushed to new prominence, new challenges and new scales – including therapeutic oligonucleotides at tonne scale, whole synthetic genomes for biotechnology and antiviral mRNA vaccines requiring the urgent production of billions of doses.