-Mouse

Mouse as a Model Organism

Mus musculus, the house mouse, has become the preferred mammalian model used for genetic research. In the past, scientists would develop mouse models by selecting and breeding specific mice to produce offspring that displayed their desired characteristics. With all of the genetic technology available now, scientists can use mice to simulate human genetic disorders in order to study their progression and to test new therapeutics. The sequence of the mouse genome was published in December of 2002. The mouse genome is about 3,500 million base pairs in length and contains over 23,000 protein-coding genes, which scientists can manipulate in a variety of ways to learn more about human development and disease. Mice have provided a key scientific tool to speed up the process of drug development and the progress of research.

Strengths

There are many benefits of using mice in research to gain insight into human physiology. These include:

• The anatomy, physiology, and genetics of mice are very similar to humans.
• The mouse genome is closely related to the human genome, which makes it easy to study human diseases using mouse genetic research.
• Mice are relatively inexpensive.
• Mice can reproduce quickly.
• The mouse is a small animal, making it easy to house and maintain.
• The generation time of a mouse is short, allowing several generations of mice to be observed at once.
• The short lifespan of a mouse allows scientists to use mice to study the effects of aging.
• Many of the genes responsible for complex diseases are shared between humans and mice, allowing mice to be used to provide insights into genetic risk factors for these diseases in humans.
• It is easy to manipulate the mouse genome, providing a tool to create models of specific diseases.
• Mice can be used to study complex biological systems and, like humans, they naturally develop diseases that affect these systems.
• Immunodeficient mice can be used as hosts to grow human tissue.

Weaknesses

Although there are many advantages to using mice as a model organism, there are also some limitations. These include:

• The mouse embryo is very small and can be difficult to work with.
• Mice have small litter sizes, and, therefore, experiments may require lots of breeding to occur.
• Because mouse embryos develop inside of the mother, they can be difficult to visualize.
• Mice require more care and maintenance than some other model organisms.
• Genetic mouse experiments can be time-consuming, expensive, and labor intensive.
• Lab mice are inbred and don’t capture the genetic variation that exists in humans.
• The responses in mice don’t always correlate with those in humans.
• Forward genetic screens are difficult and expensive.