How can genetically modified animals help scientists study human diseases?

Genetically modified animals serve as essential biomedical models that allow scientists to study human diseases in ways that are often impossible or unethical to perform directly on humans. By engineering these animals, researchers can gain profound insights into the biological roles of specific genes and their involvement in various health conditions.123

Key ways these models assist in medical research include:

• Understanding Disease Mechanisms: Scientists use techniques like homologous recombination and gene trapping to create "knockout" animals—such as mice—where specific genes are inactivated. This helps researchers observe the resulting phenotypic changes, providing clues about how those genes function and how their disruption contributes to diseases like cancer, diabetes, cystic fibrosis, and Parkinson disease.2
• Testing Novel Therapies: Genetically modified animal models provide a platform for developing and testing new drug therapies and surgical techniques. They allow for the evaluation of safety and efficacy before clinical applications.213
• Precision Editing: With the advent of tools like CRISPR-Cas9, scientists can now make highly specific changes to an animal's DNA to replicate human genetic errors, enabling the study of disease progression and even the potential for clinical rescue.4

While these models are invaluable, researchers must adhere to ethical principles, ensuring that the use of animals in research is conducted responsibly to alleviate human suffering while maintaining rigorous oversight.45