The Use of GM Crops in Developing Countries
Glossary N-Z
Plasmid:
A type of small DNA molecule that can be used to deliver a DNA sequence or gene into a cell.
Precautionary principle/precautionary approach:
A rule that permits governments to impose restrictions on otherwise legitimate commercial activities, if there is a perceived risk of damage to the environment or to human health. Its interpretation is disputed (see Box 4.1).
Promoter:
A short DNA sequence that regulates the expression of a gene. Each gene has its own promoter, to which specialised proteins bind in order to activate it.
Proteins:
Biological molecules that are essential for all life processes and are encoded by an organism’s genome. A protein consists of chains of amino acid subunits and its function depends on its three-dimensional structure, which is determined by its amino acid sequence.
Purchasing power parity (PPP):
A method of measuring the relative purchasing power of different countries’ currencies over the same types of goods and services. Because goods and services may cost more in one country than in another, PPP aims to make more accurate comparisons of standards of living across countries. However, since not all items can be matched exactly across countries and time, the estimates are not always robust.
Refuges:
Areas of crops which are susceptible to weeds or, more usually, insects, and thus provide a safe haven for them. These are maintained near fields of herbicide tolerant or insect resistant crops with the aim of providing a supply of insects and weeds that remain susceptible to the respective toxin. The strategy is designed to greatly decrease the odds that a resistant insect can emerge from the herbicide tolerant or insect resistant field and choose another resistant insect as a mate. By preventing the pairing of genes conferring resistance, these refuges help ensure that susceptibility is passed on to offspring.
Resistance:
The ability to withstand abiotic or biotic stress, or a toxic substance. Resistance, relative to susceptibility, is genetically determined. Forms of biotic resistance are pest resistance, insect resistance, bacterial resistance and fungal resistance.
Rotavirus:
A virus which causes acute gastroenteritis. Symptoms include vomiting and diarrhoea.
Self-pollination:
Plants that pollinate their own flowers. See also open-pollination.
Subsidiarity:
According to the principle of subsidiarity, within a system of governance, decisions should be taken at the lowest possible level, provided that goals such as safety and environmental protection are secured.
Subsistence farmers:
Farmers who mostly grow food for themselves and their dependents, with any surplus typically being sold locally.
Substantial equivalence:
A concept that allows a novel food to be compared with a similar existing food.
Tissue culture:
The growth of cells, tissues or organs in a nutrient medium under sterile conditions.
Traceability:
The ability to trace and follow a food or feed through all stages of production, processing and distribution.
Transformation:
The process by which foreign DNA is transferred and incorporated into a living cell.
Transgene:
An isolated gene sequence used to transform an organism. The transgene may have been derived from a different species than that of the recipient.
Triploid:
An organism, or a cell type, with a chromosomal complement of three times the haploid number of chromosomes. A haploid cell (for example a pollen cell) contains a single set of chromosomes. An example of a triploid species is the cultivated banana.
Wide-crossing:
The process of undertaking a cross where one parent is from outside the immediate (primary) genepool of the other. The term usually refers to artificially induced hybridisations between cultivated crop species and wild relatives.