Editing DNA synthesis (section)

===Oligonucleotide synthesis===
[[Oligonucleotide synthesis]] is the chemical synthesis of sequences of nucleic acids. The majority of biological research and bioengineering involves synthetic DNA, which can include [[oligonucleotide]]s, synthetic genes, or even [[chromosome]]s. Today, most synthetic DNA is custom-built using the [[Nucleoside phosphoramidite|phosphoramidite]] method by [[Marvin H. Caruthers]]. Oligos are synthesized from building blocks which replicate natural bases. Other techniques for synthesising DNA have been commercially made available, including Short Oligo Ligation Assembly.<ref>https://telesisbio.com/gibson-sola-platform/</ref> The process has been automated since the late 1970s and can be used to form desired genetic sequences as well as for other uses in medicine and molecular biology. However, creating sequences chemically is impractical beyond 200-300 bases, and is an environmentally hazardous process. These oligos, of around 200 bases, can be connected using DNA assembly methods, creating larger DNA molecules.<ref>{{cite journal |last1=Palluk |first1=Sebastian |last2=Arlow |first2=Daniel H |display-authors=et al <!--Sebastian Palluk, Daniel H Arlow, Tristan de Rond, Sebastian Barthel, Justine S Kang, Rathin Bector, Hratch M Baghdassarian, Alisa N Truong, Peter W Kim, Anup K Singh, Nathan J Hillson & Jay D Keasling -->|title=De novo DNA synthesis using polymerase-nucleotide conjugates |journal=Nature Biotechnology |date=2018 |volume=36 |issue=7 |pages=645–650 |doi=10.1038/nbt.4173|pmid=29912208 |osti=1461176 |s2cid=49271982 }}</ref>

Some studies have explored the possibility of enzymatic synthesis using [[terminal deoxynucleotidyl transferase]] (TdT), a DNA polymerase that requires no template. However, this method is not yet as effective as chemical synthesis, and is not commercially available.<ref>{{cite journal |last1=Perkel |first1=Jeffrey M. |title=The race for enzymatic DNA synthesis heats up |journal=Nature |date=2019 |volume=566 |issue=7745 |page=565 |doi=10.1038/d41586-019-00682-0 |pmid=30804572 |bibcode=2019Natur.566..565P |doi-access=free }}</ref>

With advances in artificial DNA synthesis, the possibility of [[DNA data storage]] is being explored. With its ultrahigh storage density and long-term stability, synthetic DNA is an interesting option to store large amounts of data. Although information can be retrieved very quickly from DNA through next generation sequencing technologies, de novo synthesis of DNA is a major bottleneck in the process. Only one nucleotide can be added per cycle, with each cycle taking seconds, so the overall synthesis is very time-consuming, as well as very error prone. However, if biotechnology improves, synthetic DNA could one day be used in data storage.<ref>{{cite journal |last1=Tabatabaei |first1=S. Kasra |title=DNA punch cards for storing data on native DNA sequences via enzymatic nicking |journal=Nature Communications |date=2020 |volume=11 |issue=1 |page=1742 |doi=10.1038/s41467-020-15588-z|pmid=32269230 |pmc=7142088 |bibcode=2020NatCo..11.1742T |doi-access=free }}</ref>