Hell's Gift

In Greek mythology, Chimera was a monstrous fire-breathing female creature of Lycia in Asia Minor, composed of the parts of multiple animals: upon the body of a male lion with a tail that terminated in a snake's head, the head of a goat arose on her back at the center of her spine. Chimera was one of the offspring of Typhon and Echidna and a sibling of such monsters as Cerberus and the Lernaean Hydra. The term chimera has also come to mean, more generally, an impossible or foolish fantasy, hard to believe.

Typically seen in non-human zoology (but also discovered to a rare extent in humans), a chimera is an animal that has two or more different populations of genetically distinct cells that originated in different zygotes involved with sexual reproduction; if the different cells emerged from the same zygote, it is called a mosaicism.


Chimeras are formed from four parent cells (two fertilized eggs or early embryos fused together). Each population of cells keeps its own character and the resulting animal is a mixture of tissues.


This condition is either inherited, or it is acquired through the infusion of allogeneic hematopoietic cells during transplantation or transfusion. In nonidentical twins, chimerism occurs by means of blood-vessel anastomoses. The likelihood of offspring being a chimera is increased if it is created via in vitro fertilization. Chimeras can often breed, but the fertility and type of offspring depends on which cell line gave rise to the ovaries or testes; varying degrees of intersexuality may result if one set of cells is genetically female and another genetically male.