polysomy


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polysomy

[päl·ē‚sō·mē]
(genetics)
The occurrence in a nucleus of an extra copy of one or more individual chromosomes.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
Although trisomy 8 is one the most common chromosomal abnormalities observed in hematological malignancies (4), polysomy 8 is a rare, non-random numerical abnormality associated with myeloid malignancies such as acute myelod leukemia (AML), myelodysplastic syndromes (MDS) and rarely myeloproliferative disorders (MPDs) (4, 5).
Genomic studies (28,29) have shown chromosome 17 polysomy to be a rare event in breast carcinomas.
Chang et al., "Prenatal diagnosis and genetic analysis of X chromosome polysomy 49,XXXXY," Prenatal Diagnosis, vol.
Among the positive specimens, seven exhibited EGFR gene amplification and 13 exhibited high polysomy of EGFR gene.
Role of polysomy 17 in transitional cell carcinoma of the bladder: immunohistochemical study of HER2/neu expression and fish analysis of c-erbB-2 gene and chromosome 17.
Several studies reported that the development of resistance to anti-EGFR therapies was associated with acquired gains of KRAS that occurred either as novel focal amplifications or as high-level polysomy of chromosome 12p (60, 61) and that resistant clones in the circulation were detectable months before progression was clinically obvious (60, 62).
Furthermore, after G-banding the most frequent engagement in polysomy was of the X chromosome.
In order to avoid misinterpreting chromosome 17 polysomy as HER2 gene amplification, the use of a CEN 17 probe is recommended for more accurate HER2 status assessment.
In-situ hybridization using probes for highly repeated sequences located in the centromere regions of specific chromosomes was then used on tissue sections of these specimens to detect chromosome polysomy, or the presence of cells with three or more chromosome copies.
Cases with >2.7 chromosome 17 per nucleus on average were considered as polysomy.