Animals are used in four main areas of biomedical research and product testing:

• Applied research
• Basic biological and medical research
• Regulatory testing
• Breeding of laboratory animals

Cosmetic testing on animals was banned across the UK in 1998.

Household product testing was banned in 2015.

Applied research

To conquer disease a lot of work is put into developing better medicines and surgical operations, as well as making vaccines and finding other ways of preventing diseases. Much of this work is for human medicine; some is to treat diseases suffered by both humans and animals, and some is specially for animal medicine.

The development of polio and diphtheria vaccines, insulin for diabetes, and kidney transplants are all examples of medical advances that depended on animal research. This sort of research will be needed for the new medicines and other treatments of the future. There are many diseases that we cannot yet cure, such as multiple sclerosis and certain cancers, as well as new diseases like AIDS; and in many cases animal research is playing an important part in the search for cures.

As this is a relatively large area of research and testing it is useful to split it into three main areas. Animals are vital in all three.

• basic research to find new vaccines and treatments
• applied research developing new medicines and vaccines and improving existing ones
• regulatory testing potential new medicines to make sure they are effective and safe

The last of these, safety testing, is carried out only after the potential medicine has come through many tests on isolated cells and tissues. Safety testing accounts for less than half of animals in this category, or 7% of animals used in all medical research. Safety testing is vitally important - and it's a legal requirement - before tests on human volunteers and patients in clinical trials. A new medicine is usually tested on more humans than animals before it is allowed to be prescribed by doctors.

Applied research accounts for just under 10% of all animal procedures carried out in the UK. Click here for more information on numbers of animals used in the UK, including the latest statistics.
 

Basic research

Fundamental (or basic) research in medicine and biology is done  to try to find out more about what keeps humans and animals alive and healthy. It is important to understand exactly how the different tissues and organs of the body work when healthy, and to find out what goes wrong when disease strikes.

In the past, animal research was vital for discoveries such as how the kidneys work, or how hormones control different parts of the body. Today, basic research in many areas of biology and medicine still needs to use animals. A good example is the brain: there is still a lot we do not know about how it works and if we are to find answers to these important questions, fundamental research must continue.

Fundamental research is to medicine as the foundations are to a house: if you haven't laid the foundations properly then the house will either fall down or be impossible to build in the first place. The understanding gained by fundamental research often feeds into the more applied medical research that ultimately leads to new medicines.

Basic research accounts for just over a quarter of all animal procedures carried out in the UK. Here is more information on numbers of animals used in the UK, including the latest statistics.

Regulatory testing

The wide range of chemicals which are in everyday use - such as medicines or household products - as well as chemicals used in manufacturing, or fertilisers and pesticides used in farming, must be tested to make sure that they are as safe as possible for animals and people. Safety testing makes up a very small proportion of animal research and is done to guard against products which could cause damage like cancer or birth defects. This is essential for the health of people, animals and the environment. As well as protecting the consumer, workers involved in production and those that come into contact with chemicals during transport must be protected.

Regulatory research accounts for an eighth of all animal procedures carried out in the UK. For more information on numbers of animals used in the UK, including the latest statistics, see here.

Creation and breeding of laboratory animals

Most GM animals are used in genetic studies, and nearly all of them are mice and rats. They may be used in basic research to discover the function of a particular gene - in embryonic development or the ageing of cells, for instance - or in the study of diseases.

Terminology

There are numerous terms used to describe animals that have had their genes changed in some way. This can make things confusing; however, these terms are often used interchangeably and are considered to have similar if not identical meanings:

• Genetically altered (GA)
• Genetically modified (GM)
• Genetically engineered (GE)

The UK government makes a slight distinction between GM and GA. It classifies GM organisms as those which have been genetically changed, and GA organisms include both GM organisms and those carrying 'natural' mutations.

Other terms used include transgenic and knockout. Transgenic refers to a subtype of GM animals whose genomes have been altered by the insertion of DNA from another organism. A knockout animal has had one or more genes inactivated or silenced.

The history

In 1981 British researcher Sir Martin Evans developed a way to grow embryonic stem cells from mouse embryos. Because these cells grow indefinitely in the lab, he found it was possible to genetically alter them. When these genetically altered cells were mixed with the cells of another early embryo, they produced mice which could pass on the new genes to the next generation.

By 1989 another team had used this technique to produce knockout mice. These mice can provide information about the roles of single genes in organisms. It is possible to study almost every aspect of mammalian physiology in this way. The technique has been used for research in fields as diverse as cancer, immunology, neurobiology, human genetic disorders and endocrinology.

Sir Martin himself has used knockout mice in studying cystic fibrosis and breast cancer. As the Nobel Assembly said in awarding the prize for gene targeting: “Its benefits to mankind will continue to increase over many years to come.”

GM mice are useful in the study of many diseases that are inherited or partially inherited caused by faults in an individual's genetic code.  Some serious, potentially fatal illnesses like sickle cell disease or cystic fibrosis are caused solely by having faulty genes. Some long-term illnesses such as diabetes or rheumatoid arthritis have many causes that include faulty genes, combined with other factors such as infection.

Sometimes animals have exactly the same genetic fault that humans do. For example, there is a kind of mouse which naturally develops muscular dystrophy, and this animal is important for research into that illness. However, this is not always the case, so the ability to alter genes and breed strains of mice and other animals that develop a particular inherited disease could lead to treatments for cystic fibrosis, sickle cell disease and other inherited or partially inherited diseases.

Why have the numbers risen in the last decade?

GM animals are the main reason the number of experiments in the UK has been rising in the last decade. Genetic modification (mostly of mice) now accounts for half of all animal procedures in the UK. Breeding to produce GA animals mainly involves mice (approx 88-86% per year) with the rest of all procedures mainly involving zebrafish. Click here for more information on the number of animals used in the UK, including the latest statistics.

Some animals in the breeding category are normal (not GA) parent animals; on the other hand, breeding is not the primary purpose recorded for all genetically altered (GA) animals. So, while there is considerable overlap of some one million procedures, breeding procedures and procedures involving GA animals are not the same thing. In numerical terms, this means that around a quarter of a million breeding procedures involved normal mice, while over half a million procedures involving GA mice were not primarily for breeding. These animals would have been used in other recorded procedures. Similarly, about four-fifths of GA fish procedures were primarily for breeding. A small proportion of breeding procedures involved normal fish.