The Detection of Genetically Modified Organisms: An Overview

Abstract

Genetically modified organisms (GMOs) are those whose genetic material has been altered by the insertion of a new gene or by the deletion of an existing one(s). Modern biotechnology, in particular, the rise of genetic engineering, has supported the development of GMOs suitable for research purposes and practical applications (Gepts, 2002; Novoselova, Meuwissen, & Huirne, 2007; Sakakibara & Saito, 2006). For over 20 years GM bacteria and other GM organisms have been used in laboratories for the study of gene functions (Maliga & Small, 2007; Ratledge & Kristiansen, 2006). Agricultural plants were the first GMOs to be released into the environment and placed on the market. Farmers around the world use GM soybeans, GM corn and GM cotton that are herbicide tolerant, or insect resistant, or combine several traits that reduce the costs associated with crop production (Corinne, Fernandez-Cornejo, & Goodhue, 2004). Biotech crop coverage increased globally by 13% (12 million hectares) in 2005–06 (James, 2007), and, for example, in 2007 over 70% of all soybean-producing areas were covered by GM varieties. Although transgenesis of livestock began around 20 years ago, GM farm animals, including fish, are still not as common as GM plants, the development of which began somewhat earlier. Transgenic plants are most often developed by the insertion of an alien (recombinant) gene using the soil bacteria, Agrobacterium tumefaciens, which is able to transfer a piece of its own genetic information into a plant cell. While GM plant development is at least partially based on naturally occurring mechanisms, the engineering of most transgenic livestock relies on highly technical approaches, such as pronuclear microinjection. However, newly developed techniques [sperm mediated gene transfer (SGMT), somatic cell nuclear transfer (SCNT)] have been recently introduced that enable transgenic animals to be produced more efficiently and more cheaply. These have been successfully applied to the development of several types of GM animals including cattle, sheep, pigs, chicken and fish. The potential benefits of GM animals include accelerated animal