What is genetic engineering?

Modifying the genome on purpose

Genetic engineering refers to the intentional, directed changing of an organism’s DNA, as opposed to the random changes of natural mutation or the slow process of selective breeding. Using molecular tools, researchers can add a new gene, remove or disable an existing one, or alter a sequence. The defining idea is deliberate control over an organism’s genetic make-up to produce a desired characteristic or to investigate how genes work.

Recombinant DNA technology

A foundational technique is recombinant DNA technology, which combines DNA from different sources into a single molecule. Restriction enzymes cut DNA at specific sequences and ligase enzymes join fragments together, allowing a gene from one organism to be inserted into another.

This approach, developed in the 1970s, made it possible to produce proteins in engineered cells and to study individual genes in isolation, and it underlies much of modern biotechnology.

GMOs and applications

Genetically modified organisms (GMOs) are organisms whose genomes have been altered through genetic engineering. Applications studied and used in research and industry include crops engineered for particular traits, microorganisms engineered to produce useful proteins, and model organisms designed to investigate biology. Newer, more precise gene-editing tools such as CRISPR have expanded what genetic engineering can achieve.

Research framing and oversight

Genetic engineering is governed by safety and ethical frameworks and by regulatory bodies that oversee how engineered organisms are made and used. This page describes the science, methods, and research applications of genetic engineering in neutral terms and does not provide medical or agricultural advice.