Transgenic organism

Definition

An organism whose genome has been stably altered by the introduction of one or more foreign DNA sequences (transgenes) through genetic engineering, typically integrated into the germ line so that the modification is heritable. In arthropod research, transgenic organisms are created to study gene function, developmental pathways, or disease mechanisms, and increasingly for applied purposes such as sterile insect technique or pathogen-resistant strains.

Etymology

From trans- (across, beyond) + -genic (producing, related to genes), referring to genes transferred across species boundaries; organism from Greek organon (tool, instrument, body part).

Example

Transgenic strains of Drosophila melanogaster carrying reporter genes like GFP allow researchers to visualize real-time gene expression patterns during embryonic development; similarly, transgenic Aedes aegypti mosquitoes have been engineered with gene drives to suppress wild populations that transmit dengue virus.

Synonyms

• genetically modified organism
• GMO

Related Terms

• Transgene
• transgenesis
• gene drive
• reporter gene
• germ-line transformation
• knock-in
• knockout
• CRISPR
• Drosophila genetics
• sterile insect technique

Usage Notes

Distinguished from transient transfection (temporary, non-heritable gene expression) and from organisms modified through selective breeding or induced mutation without foreign DNA insertion. In entomology, transgenic approaches differ from Wolbachia-based cytoplasmic incompatibility or irradiation-based sterile insect release, though these methods may be combined. The term is sometimes used more loosely in popular contexts; specialists reserve it for stable germ-line integration of engineered constructs.