Gene Synthesis Machines, DNA Molecules, Gene Synthesis Machines, Microprocessor, Deoxyribonucleotidies

	Gene Synthesis Machines - Methods for synthesis of DNA molecules of known base sequences have improved dramatically during 1980s and 1990s. Therefore, genes can now be synthesized rapidly and in high yields. For instance a gene for a tRNA took 20 man years effort during 1965- 70 (described earlier in this chapter), but the same gene can now be synthesized within a matter of few days with the help of Gene Synthesis Machines developed in 1980's. The key innovations which made the availability of gene synthesis machines possible, include the following
(i) development of silica based supports, which are insoluble and provide support for solid phase synthesis of DNA chains and (ii) development of stable protonated deoxyribonucleoside phos-phoramidites as synthons, which are remarkably stable towards oxidation and hydrolysis and thus are ideal for DNA synthesis. These two procedures can be used to prepare DNA molecules more than 100 nucleotides long within a few days. Different steps involved in solid phase synthesis of a DNA chain.