robertsonian translocation

(redirected from Robertsonian fusion)

translocation

 [trans″lo-ka´shun]
the attachment of a fragment of one chromosome to a nonhomologous chromosome.
Translocation of a portion of one chromosome to another chromosome. Redrawn from Damjanov, 2000.
reciprocal translocation the mutual exchange of fragments between two broken chromosomes, one part of one uniting with part of the other.
robertsonian translocation that in which the breaks occur at the centromeres and entire chromosome arms are exchanged, usually involving two acrocentric chromosomes.

ro·bert·so·ni·an trans·lo·ca·tion

translocation in which the centromeres of two acrocentric chromosomes appear to have fused, forming an abnormal chromosome consisting of the long arms of two different chromosomes with loss of the short arms. A carrier of a balanced robertsonian translocation has only 45 chromosomes but near normal chromosomal complement and a clinically normal phenotype; however, he or she is at risk of having a child with unbalanced chromosomal complement. A person with an unbalanced robertsonian translocation is trisomic for the long arm of the chromosome.
Synonym(s): centric fusion
[W.R.B. Robertson, U.S. geneticist.]

robertsonian translocation

[rob′ərtsō′nē·ən]
the exchange of entire chromosome arms, with the break occurring at the centromere, usually between two nonhomologous acrocentric chromosomes. It produces one large, metacentric chromosome and one extremely small chromosome. The latter carries little genetic material and may be lost through successive cell divisions, leading to a reduction in total chromosome number. Compare balanced translocation, reciprocal translocation.
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Robertsonian translocation

ro·bert·so·ni·an trans·lo·ca·tion

(rob'ĕrt-sō'nē-ăn tranz'lō-kā'shŭn)
Translocation in which the centromeres of two acrocentric chromosomes appear to have fused, forming an abnormal chromosome consisting of the long arms of two different chromosomes; if the translocation is balanced, the individual is clinically normal but a carrier of the translocation; if the translocation is unbalanced, the individual is trisomic for the long arm of a chromosome.
Synonym(s): centric fusion.
[W.R.B. Robertson, U.S. geneticist.]

Robertson,

W.R.B., U.S. geneticist, 1881–.
robertsonian translocation - translocation in which the centromeres of two acrocentric chromosomes appear to have fused, forming an abnormal chromosome. Synonym(s): centric fusion

Robertsonian translocation

see Robertsonian translocation.
References in periodicals archive ?
irradians may not be a selective advantage, but rather because of an evolutionary loss of telomeres through Robertsonian fusion and extensive chromosome arm loss.
This reduction in chromosome number may be because of Robertsonian fusion, wherein telocentric chromosomes fused, reducing the total chromosome number (Wang & Guo 2004).
Robertsonian fusion and centric fission are unique in being readily identified in comparative karyotype studies since both result in concomitant changes in chromosome morphology and chromosome number.
Robertsonian fusion has been demonstrated as a significant mechanism of karyotype evolution in several genera of the Tradescantieae where it can be regarded as a type of chromosome ortho-selection.