chimera

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chimera

 [ki-me´rah]
an organism whose body contains different cell populations derived from different zygotes of the same or different species, occurring spontaneously or produced artificially.

chi·me·ra

(kī-mēr'ă, ki-),
1. In experimental embryology, the individual produced by grafting an embryonic part of one animal onto the embryo of another, either of the same or of another species.
2. An organism that has received a transplant of genetically and immunologically different tissue, such as bone marrow.
3. Dizygotic twins that exchange immunologically distinct types of erythrocytes.
4. A protein fusion in which two different proteins are linked through peptide bonds; usually genetically engineered. Chimeric antibodies may have the Fab fragment from one species fused with the Fc fragment from another.
5. Any macromolecule fusion formed by two or more macromolecules from different species or from different genes.
[L. Chimaera, G. Chimaira, mythic monster (lit. a she-goat)]

chimera

/chi·me·ra/ (ki-mir´ah)
1. an organism with different cell populations derived from different zygotes of the same or different species, occurring spontaneously or produced artificially.
2. a substance created from proteins or genes of two species, as by genetic engineering.chimer´ic

chimera

also

chimaera

(kī-mîr′ə, kĭ-)
n.
1.
a. An organism, organ, or part consisting of two or more tissues of different genetic composition, produced as a result of organ transplant, grafting, or genetic engineering.
b. A gene or protein consisting of parts from two different genes or proteins that are normally distinct, sometimes derived from two different species.
2. An individual who has received a transplant of genetically and immunologically different tissue.

chimera

[kimir′ə, kīmir′ə]
Etymology: Gk, khimaros, fire-breathing monster
an organism carrying cell populations derived from two or more different zygotes of the same or different species. Chimeras include recipients of tissue grafts from other individuals. Compare mosaic.

chimera

Any individual organism or molecule derived from 2 or more species.
 
Embryology
An organism that results when an embryonic part of one organism is grafted onto another.

Genetics
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.

Molecular biology
(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.

Transplantation
The term chimera was once used for a person who had received transplanted tissue—e.g., bone marrow surviving in a recipient.

chi·me·ra

(kī-mēr'ă)
1. The individual produced by grafting an embryonic part of one animal onto the embryo of another, either of the same or of another species.
2. An organism that has received a transplant of genetically and immunologically different tissue, such as bone marrow.
3. Dizygotic twins that have immunologically distinct types of erythrocytes.
4. A protein fusion in which two different proteins, usually from different species, are linked through peptide bonds; usually genetically engineered. Chimeric antibodies may have the Fab fragment from one species fused with the Fc fragment from another.
5. Any macromolecule fusion formed by two or more macromolecules from different species or from different genes.
[L. Chimaera, G. Chimaira, mythic monster (lit. a she-goat)]

chimera

An organism that contains a mixture of genetically different cells derived from more than one ZYGOTE. A chimera may, for instance, occur as a result of fertilization by more than one spermatozoon; fusion of two zygotes; an ALLOGENEIC bone marrow graft; cell exchange between dizygotic twin fetuses; or combination of portions of embryos of different species. Compare MOSAICISM. The term derives from the name of a mythical monster with a lion's head, a goat's body, and a serpent's tail.

chimera, chimaera

1. a mythological, fire-spouting monster with a lion's head, goat's body and serpent's tail.
2. an animal whose body contains different cell populations derived from different zygotes of the same or different species, occurring spontaneously or produced artificially; i.e. an individual composed of a mixture of genetically different cells.

chimera protein
see fusion protein.
References in periodicals archive ?
As expected, harboring at least one In2G mutation (as in chimeras CH-1, CH-2, CH-3, CH-5, CH-6, and the newly identified CH-8) was associated with the SW type of CAH, thus constituting the classic group.
Used in conjunction with in vitro fertilization, this would eliminate the need for female XO/XX chimeras, although a surrogate mother would still be needed to carry the two-father pregnancy to term.
In fact, scientists can create human-nonhuman chimeras in many ways.
Countries that can hardly be described as pro-West will inevitably combine human-animal chimera technology with cloning technology to create 'special forces'.
Religious leaders concerned about human dignity are not the only forces raising questions about chimeras.
The term chimera comes from the Greek word for a monster that was part lion, part goat and part serpent.
But not everyone is excited about the prospects of creating chimeras to help humankind.
The formation of human/animal chimeras should also be banned.
Chimeras - named after a monster from Greek myth - can be formed by placing cells from a newly-conceived male embryo into a new female embryo.
Some people may express a fear, distaste, revulsion, or general anxiety about the "unnatural" mixing of species--about creating chimeras, about altering the telos of species (so as to interfere with a fish's "fishness," for example), about crossing the species barrier, and about the intertwining of human and animal genes.
Silverstone used radiation chimeras to examine the contribution of specific cells to the estrogen or dioxin response.
In Dreamers of Decadence, Philippe Julian dedicated four chapters to the legendary, mystical, macabre and erotic Chimeras respectively,(6) not to mention two additional ones entitled: 'The Chimera Catchers' and 'Breeding the Chimeras', in which the word is used not in its literal but rather in its metaphorical sense--following the dictionary definition as ' any idle or wild fancy'.