What Are Chimera Animals?

Chimera animals are specimens that have at least two sets of genetically different cells. Having more than one set of DNA typically is the result of scientists inserting stem cells into an animal from another animal or even from a different species. For example, in 2011, US scientists were able to create three normal, healthy chimera monkeys whose DNA came from as many as 12 parents by implanting cells from embryos into female monkeys. Scientists believe that by studying chimera animals, they will be able to learn more about how stem cells work, which could help scientists find cures for conditions thought to be caused by damaged cells, such as paralysis and Parkinson’s disease.

More about chimeras:

• In 2003, Chinese scientists created the first chimera animal with human cells by fusing rabbit eggs with human cells.
• Chimera animals are named after the chimera in Greek mythology — a fire-breathing creature that had a goat's body, lion's head and serpent's tail.
• Canada passed a ban in 2004 on chimeras specifically made by transferring human cells or embryos into animals.

Frequently Asked Questions

What exactly is a chimera animal?

A chimera animal is a single organism composed of cells with distinct genetic makeups, resulting from the merging of multiple fertilized eggs. This can occur naturally or be engineered through scientific methods. In nature, chimerism can lead to animals with physical characteristics that are a blend of different genetic profiles.

How does an animal become a chimera?

An animal can become a chimera through natural processes, such as the fusion of multiple embryos in the womb, or through artificial means, like laboratory manipulation where scientists combine cells from different embryos. This can happen in mammals, including humans, when two fertilized eggs fuse together early in development.

Can chimerism be detected in all animals?

Chimerism is not always detectable by appearance alone, as many chimeras look like normal animals. It often requires genetic testing to confirm. For instance, blood tests can reveal different blood types coexisting in one individual, which is a strong indicator of chimerism, according to scientific research in genetics.

Are there any health implications for chimera animals?

Chimera animals can lead healthy lives, but they may face unique health challenges. For example, if their immune system contains cells from genetically distinct populations, it could lead to autoimmune conditions. Veterinary research suggests that careful monitoring is essential for maintaining the health of chimeric animals.

What is the difference between a chimera and a hybrid animal?

A chimera is an organism with cells from two or more different zygotes, while a hybrid results from the breeding of two different species or subspecies. Hybrids have a uniform set of genes throughout their body, whereas chimeras possess different genetic information in various parts of their body.

Are there any famous examples of chimera animals?

One of the most famous examples of a naturally occurring chimera is a cat known as a "tortoiseshell" or "calico," which can exhibit distinct patches of color indicative of chimerism. In scientific research, genetically modified mice have been created as chimeras to study gene function and disease.