Glossary: Genetic Technology

This chapter's terms in context

Chapter 28 closes the syllabus with four terms describing how humans deliberately manipulate genetic material and living organisms for practical purposes: biotechnology, genetic engineering, genetically modified organism (GMO) and cloning. Biotechnology is the broadest of these four terms, defined as the use of living organisms, or parts and products of living organisms, to develop useful products or processes for human benefit; this broad definition covers activities as old as using yeast to make bread and as recent as producing human insulin using genetically engineered bacteria, which is exactly why biotechnology functions as the umbrella category under which the other three terms in this chapter sit as more specific, modern examples.

Genetic engineering is a specific, modern branch of biotechnology that directly and deliberately alters an organism's genetic material by inserting, removing or modifying specific genes, typically involving the transfer of a gene of interest from one organism (often a different species entirely) into the genome of another, using tools such as restriction enzymes to cut DNA at specific sequences and ligase enzymes to join DNA fragments together. A frequent exam error is describing any modern biotechnology application as genetic engineering, when the defining, specifically testable feature of genetic engineering is the direct, deliberate manipulation of an organism's genes at the DNA level, distinct from other biotechnology techniques that do not alter genetic material directly, such as simply culturing existing microorganisms for fermentation.

A genetically modified organism (GMO) is the organism that results once genetic engineering has been used to alter its genetic material, typically to introduce a specific new characteristic it did not previously have, such as a crop plant engineered to resist a particular pest or herbicide, or a bacterium engineered to produce a specific human protein such as insulin. It is important to keep genetic engineering (the technique, the process itself) and GMO (the resulting organism, the product of that process) as two clearly distinct terms in an answer, rather than treating them as synonyms describing the same single idea, since a question may ask specifically about the process in one part and the resulting organism in another.

Cloning is a distinct biotechnology technique that produces one or more genetically identical copies of an organism, a cell, or a piece of DNA, and it does not necessarily involve altering any genetic material at all, unlike genetic engineering, cloning is fundamentally about exact genetic duplication rather than deliberate genetic modification. Cloning can occur at different levels: a whole organism can be cloned (as with a cloned animal produced by nuclear transfer), or a specific gene or DNA fragment can be cloned (gene cloning, often as part of a larger genetic engineering procedure to produce many copies of a gene of interest before it is inserted into a host organism). A common structural confusion is treating cloning and genetic engineering as the same process because both appear together in modern biotechnology procedures, when in fact cloning by itself produces an identical copy, while genetic engineering by itself produces a deliberately altered, non-identical organism, and a full biotechnology procedure may use both techniques together in sequence without the two terms describing the same step.

Paper 2 questions on this chapter frequently ask a candidate to place a described real-world application (such as producing human insulin from bacteria, cloning a sheep, or growing a pest-resistant crop) into the correct one or two of these four categories, and full marks depend on justifying the classification with the specific defining feature of each term rather than only naming the category.