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

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

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.
References in periodicals archive ?
Most important, you can tell our lawmakers that we want this law passed by signing the Shark, Ray, and Chimaera Conservation Act online."
The workshop and researches evaluated the extinction risk status of sharks, rays and chimaeras found in the Arabian Sea and its adjacent waters (Red Sea, Gulf of Aden, and Arabian Gulf) for the IUCN Red List of Threatened Species.
GREEK mythology has stories about Chimaera, a monstrous fire- breathing lion, goat and snake hybrid and one has been recently caught off the coast of Newfoundland.
[8.] Stevens JD, Bonfil R, Dulvy NK, Walker PA (2000) The effects of fishing on sharks, rays and chimaeras (chondrichthyans) and the implications for marine ecosystems.
The effects of embryo stage and cell number on the composition of mouse aggregation chimaeras. Zygote 8:235-243.
Overfishing is the main threat to the species, according to the paper.Reported catches of sharks, rays and chimaeras peaked in 2003 and have been dominated by rays for the last 40 years.Actual catches are likely to be grossly under-reported.
Researchers assessed the conservation status of 1,041 shark, ray and chimaera species, which are all so-called "cartilaginous fish," meaning they have skeletons made of cartilage rather than bone.
In his nonfictional family, Hawthorne saw in Julian's childish pastimes--what he describes in "Twenty Days with Julian" as imaginary "warfare" with "hydras, chimaeras, dragons, and Gorgons" (8:445)--the monstrous battles that would be the business of his adult life.
The effects of fishing on sharks, rays, and chimaeras (Chrondrichthyans), and the implications for marine ecosystems.
After Richard Lawrence's failed attempt to assassinate Jackson, the Washington Globe blamed Clay and Calhoun for provoking the assault, describing Lawrence as "infatuated with the chimaeras which have troubled the brains of the disappointed orators who have depicted the President as a Caesar who ought to have a Brutus." Richard rejects the Globe's analysis with typical humor: Lawrence was "a delusional house painter who had probably sniffed too much lead paint." But classical parallels did influence Americans.
Vladimir Gvozden introduces the reader in the fourth chapter of the volume titled 'Writing Difference/ Claiming General Validity: Jovan Ducic's Cities and Chimaeras and the West'.