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Course: Class 12 Biology (India) > Unit 11
Lesson 1: IntroductionTransgenic animals
What are transgenic animals and why do we need them?
This article offers an overview of what transgenic animals are, and why they are useful to humans.
Key terms
| term | meaning |
|---|---|
| transgenic | an organism whose genome has been altered to contain a foreign gene |
| genome | the genetic material present in an organism |
What is a transgenic animal?
Have you heard of the term 'transgenic animal'? What animal comes to mind when you image one? Rats? Guinea pigs?
Which of the following organisms could be made into transgenic animals?
That's right - all of the above animals could be made transgenic! What's common between these animals? It might not seem obvious at first glance, but there is a large overlap in the way all vertebrate organisms are wired (from genes to nervous systems). Humans, therefore, have a diverse range of animals to use or study for their benefit.
Any animal whose DNA has been modified to include one or more foreign genes is a transgenic organism. Why do we need these modified organisms? Read on to find out more!
Why do we need transgenic animals?
Why would we want to add foreign genes into animals? These genetically modified animals can be very useful tools for humans. Here are some of their common uses:
Research
Animals like mice and fish are commonly used in research labs because they offer certain advantages. For example, mice share most of their genes with humans, and zebrafish larvae are transparent, making it easy to study their organs.
Transgenic animals are used to study how different human genes work under normal conditions. Similarly, scientists can also use such animals to work out what role genes or proteins play under abnormal conditions, or in diseases like cancer, or Alzheimer's.
Drug testing
Once we've understood the causes of diseases, the next step is to find treatments or cures for the same. Pharmaceutical drugs, or medicines, and even vaccines are usually tested first on transgenic animals that can mimic human diseases. This allows us to understand how effective a drug is, and what its side effects are, before it is given to humans.
Production of human, or other proteins
Transgenic animals can carry human genes, from which they can then produce proteins. We humans can then obtain purify these proteins from the animals very simply - for example from the milk of cows or goats! This gives us an easy way to manufacture large amounts of important products like antibodies, or therapeutics like clotting factors, or even just protein-rich milk for us to consume. Similarly, transgenic animals can also be made to express non-human foreign genes in order to harvest their proteins.