A woman's body has been found to consist of varying proportions of male and female cells because of an extremely rare form of ...

Doctors in Brazil discover and confirm that a woman has blood with male chromosomes, a rare case of human chimerism.

I've long been a big fan of Greek mythology and all the wondrous beasts that tested, and sometimes bested, mythical heroes. One such creature was the chimera, a grotesque hybrid of a lion, goat, and ...

A video of an oddly colored cat is causing a stir online as people debate whether its strange, patchwork coloration is just another type of calico cat or whether it is indicative of an even more rare ...