chimaera(redirected from Chimæra)
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chimeraAny individual organism or molecule derived from 2 or more species.
An organism that results when an embryonic part of one organism is grafted onto another.
An organism with 2 or more cell lines, genotypes or karyotypes descended from at least 2 zygotes. Chimeras are very rare, only occur in twins and result from chorionic vascular anastomoses, transplantations or double fertilisations and subsequent participation of both fertilised meiotic products in one developing embryo; all hermaphrodites should be karyotyped to evaluate possible chimerism.
(1) An animal formed from two different embryonic sources. In mouse genetics, targeted mutations produced in embryonic stem cells are recovered by breeding chimeric mice, resulting from the mixture of embryonic stem cells with a genetically distinct blastocyst.
(2) A clone containing genomic DNA from nonadjacent genomic segments or cDNA from two different mRNAs.
The term chimera was once used for a person who had received transplanted tissue—e.g., bone marrow surviving in a recipient.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.
- (also called graft-hybrid) an organism, usually a cultivated plant, whose tissues are of more than one genetical type as a result of mutation or grafting.
- a smooth-skinned cartilaginous deep-sea fish (‘king of the herrings’) of the subclass Holocephali, which were common in the Jurassic.
- a DNA hybrid molecule: a composite DNA molecule produced by GENETIC ENGINEERING, made up of DNA fragments from more than one organism. It is named after the Chimaera of Greek mythology, a beast with the head of a lion, the body of a goat and the tail of a serpent.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005