Gene synthesis or DNA printing is a scientific method to create artificial genes in laboratory. Chemical synthesis of DNA sequence is done which represents the genes. Which are basically long chains of natural or non natural nucleic acid sequences. There is also a possibility of introducing new base pairs which allows creation of new genetic codes. It is a part of synthetic biology and is different from polymerase chain reaction (PCR) and molecular cloning in that the user does not need to start with the DNA sequences which are already existing; the process is based on solid phase DNA synthesis through which a completely new double-stranded DNA molecule can be prepared which would have no limits on the size and sequence of nucleotides. This method has been used to create bacteria and yeast chromosomes with a million of base pairs. Current gene synthesis is done by techniques which are a combination of molecular biology and organic chemistry.
The concept first was introduced by Sir Alexander Todd, who in the year 1955 publishes the chemical method for creation of a phosphate link between 2 thymidine nucleosides resulting in creation of DNA molecule. He won Noble Prize in 1957 for his pioneering work. The first gene synthesis was done by Har Gobind Khorana and his team in 1972, in which complete genetic sequence of yeast tRNA was done. First genetic synthesis of peptide and protein coding genes was done by of Herbert Boyer and Alexander Markham, respectively. Genscript is currently the largest artificial gene synthesis supplier of the world and was found in the year 2002. In 2011, Sc2.0 Project was launched for building the first Eukaryotic genome.
Major steps in Gene Synthesis:
1. Selection of DNA sequence
2. Sequence optimization followed by oligo design
3. Oligo synthesis
4. Assembly of genes
5. Vector of choice cloning
6. Quality control and error correction
7. Downstream application