ABSTRACT
This chapter discusses the basic techniques and progress of recombinant deoxyribonucleic acid (DNA) technology. DNA fragments generated by restriction endonuclease digestion or other techniques are usually separated by gel electrophoresis on the basis of their length and the molecular weight of the DNA fragment can easily be estimated. The polymerase chain reaction (PCR) was developed and is widely used in genetic engineering, since it provides a quicker and less expensive alternative for cloning. With the PCR technique, selective DNA fragments can be amplified to sufficient amounts even for gel electrophoresis from a trace amount of DNA. The microchip enables the DNA sequence determination and detection of single nucleotide polymorphism via the genetic diversity that causes genetic diseases as well as measurements of messenger ribonucleic acid expression levels. A chemical method which used DNA polymerase to make partial copies of the fragment to be sequenced was also developed by F. Sanger.
