polysomy


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polysomy

 [pol″e-so´me]
an excess of a particular chromosome.

pol·y·so·my

(pol'ē-sō'mē),
State of a cell nucleus in which a specific chromosome is represented more than twice. Cells containing three, four, or five homologous chromosomes are referred to, respectively, as trisomic, tetrasomic, or pentasomic. Compare: polyploidy.
[poly- + G. sōma, body (chromosome)]

polysomy

/poly·so·my/ (pol´e-so″me) an excess of a particular chromosome.

polysomy

[pol′isō′mē]
the presence of more than two copies of a chromosome in an otherwise diploid somatic cell as the result of chromosomal nondisjunction during meiosis. The chromosome may be duplicated three (trisomy), four (tetrasomy), or more times. Males with Klinefelter's syndrome may have a genotype of XXY, XXXY, or XXXXY. Polysomic females with three, four, or five X chromosomes may have a higher frequency of mental retardation.

pol·y·so·my

(pol'ē-sō'mē)
State of a cell nucleus in which a specific chromosome is represented more than twice. Cells containing three, four, or five homologous chromosomes are referred to, respectively, as trisomic, tetrasomic, or pentasomic.
Compare: polyploidy
[poly- + G. sōma, body (chromosome)]

polysomy

an excess of the numbers of a particular chromosome present.
References in periodicals archive ?
Impact of polysomy 17 on HER-2/ neu immunohistochemistry in breast carcinomas without HER-2/neu gene amplification.
The influence of polysomy 17 on HER2 gene and protein expression in adenocarcinoma of the breast: a fluorescent in situ hybridization, immunohistochemical, and isotopic mRNA in situ hybridization study.
Kaufman reported that it added no benefit for 103 women who were HER2-negative and did not have polysomy of chromosome 17.
Does chromosome 17 centromere copy number predict polysomy in breast cancer?
An increased copy number of native ALK signals due to chromosome 2 polysomy is common and reflects the overall aneuploidy of NSCLC (Figure 2, A and B).
114) However, the control regions are difficult to select given that segmental amplifications of chromosome 17, or polysomy 17, may or may not be present in a given tumor.
Polysomy was defined using FDA-approved criteria as cells with gains (3 or more copies) in 2 or more chromosomes (eg, 2:3:4:2).
13) Polysomy of 1p, 19q, or both is also noted in a subset of oligodendrogliomas and has been associated with a poor prognosis, independent of deletion status.
EGFR gain is in fact a frequent event in lung ACA, often in the context of balanced polysomy of chromosome 7, and thus is a relatively nonspecific phenomenon.
Although 10% to 50% of breast carcinomas have more than 2 CEP17 copies, only 1% to 2% of carcinomas show true polysomy (ie, duplication of the entire chromosome).