Why use the mouse in research?

Key facts

• Over the past century, the house mouse (Mus musculus) has become the preferred mammalian model for genetic research.
• In the early days of biomedical research, scientists developed mouse models by selecting and breeding specific mice to produce offspring with certain desired characteristics.
• Now scientists use mice to simulate human genetic disorders in order to study their development and test new therapies.
• As a scientific tool, mice have helped to speed up the progress of research and enabled the development of important new drugs.
• The genome sequence of the mouse was published in December 2002.
• Its genome is approximately 3,500 million base pairs in length and contains over 23,000 protein-coding genes (Ensembl).

An adult black mouse.
Image credit: Wellcome Library, London

Benefits of the mouse

• The mouse has many similarities to humans in terms of anatomy, physiology and genetics.
• The mouse genome is very similar to our own, making mouse genetic research particularly useful for the study of human diseases.
• Mice are cost effective because they are cheap and easy to look after.
• Adult mice multiply quickly. They can reproduce as often as every three weeks (they mate on the day they give birth), so scientists have lots of mice to work with.
• The mouse is small, so convenient to house.
• The time between a mouse being born and giving birth (generation time) is short, usually around 10 weeks. This means several generations can be observed at once.
• The mouse has a short lifespan (one mouse year equals about 30 human years) which means scientists can easily measure the effects of ageing.
• Mice are extremely useful for studying complex diseases, such as atherosclerosis and hypertension, as many of the genes responsible for these diseases are shared between mice and humans. Research in mice provides insights into the genetic risk factors for these diseases in the human population.
• It is relatively easy to manipulate the mouse genome, for example, adding or removing a gene to better understand its role in the body. This provides a powerful tool for modelling specific diseases when a mutated gene is known to play a role in the disease.
• Mice are far better than flies or worms for studying complex biological systems found in humans, such as the immune, endocrine (delivers hormones into the body), nervous, cardiovascular and skeletal systems. Like humans, mice naturally develop diseases that affect these systems, including cancer and diabetes.
• Immunodeficient mice (mice without a fully functioning immune system) can also be used as hosts to grow both normal and diseased human tissue. This has been a useful tool in cancer and AIDS research.