Chapter Overview

The study of DNA has developed into a large-scale industry for manipulating and modifying the genetic material of organisms.
This science, called biotechnology, aims to develop products, microbes, plants, and animals for use in commercial, agricultural, research, and medical applications.
DNA is the focus of bioengineering, or genetic engineering technology, which is based on the ease with which DNA can be isolated, handled, and modified.
The DNA double helix readily parts into its two strands; it can be cut with endonucleases, and inserted at exacting sites on other DNA.
Segments of DNA can be separated by electrical currents, synthesized by machine, and visualized by means of probes, which are some of the bases of identification.
Technology has developed methods for sequencing DNA that reveal the order of nucleotides it contains; DNA can also be amplified by the polymerase chain reaction DNA.
Recombinant DNA (rDNA) technology is a branch of genetic engineering that inserts foreign genes into cells, thereby creating modified organisms that can express these donated genes.
This process of inserting and propagating DNA is called cloning, and it requires special vectors to transport the genes into cloning hosts for maintenance and expression.
Cloning creates microbes that carry isolated genes from other organisms, giving rise to living gene libraries that can provide a source of known DNA for study and commercial uses.
Recombinant cloning hosts can be induced to synthesize the products coded for by the gene, thereby providing a source of hormones, drugs, enzymes, immune factors, and other commercial substances.
Techniques similar to rDNA are used to create genetically modified organisms such as microbes, plants, and animals that are transfected with selected genes to create new strains for medical, agricultural, genetic research, and pharmaceutical purposes.
Genetic treatments are a method for correcting inherited defects by inserting the natural, normal gene back into the genome through viruses and other techniques.
Genomes of organisms can be ordered in a map that shows the order of large genetic elements, genes, and even nucleotides that are essential for analyzing the structure and functions of the genes it contains.
Genetic fingerprinting is a method of arraying an entire genome in a way to show its unique qualities so it can be used in comparisons and identification. It is an essential tool of forensics, pedigree analysis, and microbe identification.
Bioethics is the field that analyzes the effects of the new DNA technology on society. It will be critically involved in helping develop guidelines for managing the many issues that it creates.

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