Biotechnology is a collection of technologies that enable us to manipulate living organisms or their sub-cellular components to develop useful products, processes or services.
Thousands of years ago people discovered that micro-organisms could be used in fermentation processes to make bread, brew beer and produce cheese. Later they learnt to breed sheep for better wool or cows to produce more milk. These are all early biotechnology experiments!
Through breeding and selection our ability to change and control an organism's characteristics grew increasingly sophisticated; just think how, by starting with the wolf, man has developed several hundred different breeds of dogs!
The advent of recombinant DNA technology in the 1970s allowed us to manipulate the genetic makeup of living organisms with accuracy and precision. This technology together with the development of methods to express and purify large amounts of proteins and other biological molecules heralded the birth of modern biotechnology.
What is DNA?
Deoxyribonucleic acid, DNA, carries hereditary information from generation to generation of a species.
The chemical and physical properties of DNA are ideal for both its replication and the transfer of information. Each DNA molecule is a long two-stranded chain. The strands are made up of subunits called nucleotides, each containing a sugar (deoxyribose), a phosphate group, and one of four nitrogenous bases, adenine, guanine, thymine, and cytosine, denoted A, G, T, and C, respectively.
A gene is, in essence, a segment of DNA that has a particular purpose, i.e., that codes for (contains the chemical information necessary for the creation of) a specific protein or ribonucleic acid (RNA) that co-operates with other gene products to give a phenotype, for example eye or hair colour. Genes govern both the structure and metabolic functions of the cells, and thus of the entire organism and, when located in reproductive cells, they pass their information to the next generation.
Genes are linked together on long strands of DNA which are known as chromosomes (so named by the early microscopists for their readiness to absorb dyes). The nucleus of each eukaryotic (nucleated) cell has a complete set of chromosomes (23 pairs for humans) and therefore a complete set of genes. Genes undergo a process called transcription where an RNA copy of the DNA sequence is made. The majority of these RNAs act as messengers and are translated by the ribosome to give protein.
Recent research has shown that a large number of RNAs are not messengers but have functions in their own right, a good example being the ribosome itself where the RNA molecules catalyse the production of protein.
Biotechnology is beginning to exploit the activities of RNA but most effort has gone into developing proteins as products. Proteins are made of chains of amino acids that adopt a precise three-dimensional structure and this in turn directs the activity of the protein. If the protein does not fold into this structure during its production then it will not function. NPL is developing methods to accurately measure the structure of protein biotechnology products and so determine if the product has activity.
Human and Animal Health
The health area is the primary focus of biotechnology.
The biomedical biotechnology industry is now valued at $25billion with drugs developed to treat cancer, diabetes, and inherited and infectious diseases.
A significant part of biomedical biotechnology is the description of the human DNA sequence, the Human Genome Project, which will enable every human gene product to be described.
The new disciplines of genomics and proteomics are being applied not only to humans, but to a large number of organisms to enable the identification of disease-causing genes and proteins and this information is being used to develop new drugs, vaccines and improved diagnostic methods for detecting diseases.
The field of biotechnology also includes gene therapy, in which attempts are made to insert normal or genetically altered genes into cells to treat genetic disorders and chronic diseases.
New treatments and biotechnological tools are constantly being developed and NPL is working to develop methods of improving their accuracy, precision and reliability so that the time taken from research idea to patient treatment is greatly reduced.
Industrial biotechnology is closest to the historic beginnings of biotechnology.
The enzymes produced are used to keep bread fresh, produce fruit juices, wines, treat fabrics, leather, and are a significant part of laundry and dishwashing detergents.
Companies are constantly striving to identify new enzymes and bioactive compounds for use in any number of products.
The hunting ground is vast; less than 1% of the micro-organisms in the world have been characterised.
The animal biotechnology industry wants to proceed from the traditional and imprecise methods of breeding and selection to the development of animals with specific characteristics.
The development of transgenic animals in the lab with particular genes "knocked out" or added have provided a research tool that has revolutionised medical research into such areas as immunity, cancer and obesity.
In addition nuclear transfer technology has allowed us to clone animals, most famously Dolly the Sheep.
There are potentially many uses for transgenic animals but the ethical concerns are paramount.
Selective breeding of plants and animals, intensive use of chemicals as fertilisers, pesticides and herbicides and widespread use of equipment and irrigation have traditionally improved crop production.
These techniques have brought disadvantages such as environmental pollution from the chemicals and genetically uniform crops that are more susceptible to disease.
The hope is to use recombinant DNA techniques to introduce specific traits into plants that will improve their resistance to disease and decrease their need for fertilisers.
However there has been strong opposition to releasing such plants into the wild with both accurate and inaccurate claims made about their environmental impact. Only well controlled studies and accurate measurement will help the plant biotechnology industry to grow.
Biotechnology provides many ways of sustaining the environment.
It is used to monitor ecosystems, transform pollutants into benign substances (bioremediation), generate biodegradable materials from renewable sources and develop environmentally safe manufacturing and waste disposal methods.
Biotechnology has only recently been applied to this area and there is enormous potential for biotechnological tools to improve the environment.
So how do you do it?
There are six steps to make a biotechnology product:
- Identify the gene that directs the production of the desired substance
- Isolate the gene from the genome
- Place the gene with expression signals in a suitable DNA molecule
- Transfer the recombined DNA into an appropriate host organism
- Select the individuals who contain the recombinant DNA and express the substance
- Purify the substance
|1866, Gregor Mendel||publishes rules of trait inheritance based on his work with pea plants|
|1953, Double helix model for DNA structure||developed by James Watson, Francis Crick, Maurice Wilkins and Rosalind Franklin|
|1973, Foundation of the biotechnology industry||Stan Cohen and Herbert Boyer develop recombinant DNA|
|1983, Polymerase Chain Reaction (PCR)||gene amplification technology allowing the study of small amounts of DNA - dominates the forensic science and diagnostics industry|
|1997, Dr Ian Wilmut with Dolly||the first cloned animal|
|2001, Completion of the Human Genome Project||is announced unlocking all human genes and proteins|