Chimera

(noun. /kai-MARE-uh/) 

by Riya Gohil

What does it mean? 

A chimera is an organism that is made up of genetically different cells. An organism is most commonly composed of cells that all have the same genetic material. A chimera, on the other hand, has cells with different genetic material. Chimeras often arise from the fusion of multiple zygotes, or fertilized eggs. Another method of creating a chimera is often done in the lab and consists of isolating cells from an organism, genetically modifying those cells, and reintroducing the cells to the original organism. An example of this method is shown below. 

How do I use it in a sentence?

“This mouse is a chimera because it contains its normal cells and a patch of skin cells that we genetically modified to delete a gene.”

At least one accompanying picture 

Figure 1: An example of how chimeras are made in the lab. Cells from a mouse (yellow) have been extracted and isolated to perform a series of experiments in order to genetically modify the cell type (blue cells). Blue cells now have a different genetic make-up compared to the yellow cells. These blue cells are then introduced to the starting mouse, creating a chimera – a mouse that contains both its normal cells and genetically modified cells. Image created by author with BioRender. 

Etymology

The word chimera originated from a Greek mythological monster composed of different animal parts. In Greek mythology, a chimera is often depicted as a creature that has the body and head of a lion, a second head of a goat protruding from the back of the lion’s head, and a tail that ends in a snake’s head. 

Fields of study in which this word is commonly used

Genetics