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The Genetics of Spontaneous Abortions
Published in Howard J.A. Carp, Recurrent Pregnancy Loss, 2020
Tetraploidy (4n = 92) is less common than triploidy and rarely progresses beyond 2−3 weeks of embryonic life. Tetraploidy in embryonic tissue should be distinguished from the not uncommon, and clinically insignificant, tetraploid cells found in amniotic fluid. Their basis is multinucleated syncytiotrophoblasts. Live-born tetraploidy exists but is rare [50] and probably always actually reflects diploid/tetraploid mosaicism. Origin is probably failure of cytokinesis, as shown in molecular studies and in sync with origin of 92,XXXX and 92,XXYY [51,52].
Familial Polyposis Coli: A Model for The Study of Promotion and Transformation
Published in Herman Autrup, Gary M. Williams, Experimental Colon Carcinogenesis, 2019
Structural chromosome anomalies are associated with fetal death, various postnatal morphologic abnormalities, impairment of growth, and proneness to early cancer and death. Danes17,18 reported presence of tetraploid chromosomes in the first subcultures of GS cells but not in cells of FPC patients without extra colonic lesions. However, Delhanty et al.19 reported increased tetraploidy in 3 of the 13 FPC cells tested but not in 10 control cultures. The high tetraploidy did not increase with passage levels of skin fibroblasts from affected or control cells, and the chromosome numbers remained constant through the 18 subcultures tested. However, in some cases, presence of epithelial cells was necessary to demonstrate increased tetraploidy in cultures.17 Gardner et al.20 also observed excessive random loss or gain of individual chromosomes at the diploid and tetraploid levels, with numerous chromosomal aberrations in both lymphocytes and fibroblasts cultured from GS and FPC patients and from some intrafamily children at risk for colonic cancer. Preliminary data from this group20 indicated a possible heteromorphism of chromosome no. 2 in 17 patients with multiple colorectal adenomas and in 2 intrafamily children at risk for Gardner’s syndrome. Since 18 cell strains from healthy controls did not show the structural aberrations in chromosome no. 2, this may be a useful parameter to identify potentially cancer-prone individuals at an early age.
Muscle, Bone, and Skin Disorders
Published in Victor A. Bernstam, Pocket Guide to GENE LEVEL DIAGNOSTICS in Clinical Practice, 2019
In stage II MM with metastatic spread to lymph modes, aneuploidy reaches 86%, the rest of the cells being tetraploid. The development of multiclonality is associated with tumor progression. Quantitation of these characteristics by digital imaging systems is thought to provide useful prognostic information.
Reproductive outcomes in couples with sporadic miscarriage after embryonic chromosomal microarray analysis
Published in Annals of Medicine, 2023
Zhengyi Xia, Ran Zhou, Yiming Li, Lulu Meng, Mingtao Huang, Jianxin Tan, Fengchang Qiao, Hui Zhu, Ping Hu, Qiaoying Zhu, Zhengfeng Xu, Yan Wang
Numerical chromosomal abnormalities were the most frequent abnormal finding, including 542 (48.0%) with aneuploidies and 87 (7.7%) with polyploidies. Among the cases with aneuploidies, 95.4% (517/542) of these cases were identified as single aneuploidies, and multiple aneuploidies composed the remaining 4.6% (25/542). With the exception of chromosomes 1 and 19, single aneuploidies were detected in all chromosomes. Trisomies represented the majority among the cases with single aneuploidies (420/517, 81.2%), and others were monosomies (97/517, 18.8%). With respect to trisomies, trisomy 16 was the most common (142/420, 33.8%), followed by trisomy 22 (64/420, 15.2%) and trisomy 21 (28/420, 6.7%). Monosomies were observed in chromosomes X (95/97, 97.9%), 8 (1/97, 1.0%) and 21 (1/97, 1.0%). Among the cases with polyploidies, 85 (97.7%) were triploidy and two (2.3%) were tetraploidy. In addition, four cases (0.4%) with whole-genome UPD were identified in our cohort.
Systems analysis of barrier molecule and ARNT-related gene expression regulation in melanoma
Published in OncoImmunology, 2019
Katie M. Leick, Joseph M. Obeid, Stefan Bekiranov, Craig L. Slingluff
We have found that EDC and extended BMGs are co-expressed together and upregulated in the absence of an immune gene signature in melanoma in two independent studies. There was an absence of a survival effect in the BMG/EDCHI group in the validation data set, which may be due to the small study size or inability to control for other prognostic factors. However, our other findings were validated. Many BMGs and EDC genes are important for terminal differentiation of keratinocytes and barrier function in normal skin and are located at chromosomal locus 1q21.3. Copy number amplification of 1q21.3 is weakly associated with upregulation of 1q21.3 genes, which includes some BMG/EDC and ARNT-related genes. Tetraploidy at this locus is a marker of poor prognosis. Interestingly, 1q21.3 amplification has been identified in breast cancers at higher risk of recurrence and may be actionable therapeutically.27
Testing for genetic contributions to infertility: potential clinical impact
Published in Expert Review of Molecular Diagnostics, 2018
Csilla Krausz, Francesca Cioppi, Antoni Riera-Escamilla
Macrozoospermia or sperm macrocephalia is characterized by large-headed and multi-flagellated spermatozoa [24]. To date, AURKC gene mutations are the only validated genetic causes for this disease. This gene encodes for a component of the chromosomal passenger complex (CPC) in meiotic cells and is essential for correct meiotic chromosomal segregation and cytokinesis [25]. The most common mutation is the deletion of a cytosine in the exon 3 (c.144delC), which is observed in more than 85% of the patients affected by macrozoospermia [26]. Interestingly enough, the mutation is relatively common in heterozygosis in the Maghrebian population (1/50 men) and it has been proposed that heterozygote carriers may have a selective advantage due to a more relaxed meiotic checkpoint [27]. In Europeans, a recurrent stop gain mutation in exon 6 (p.Y248*) has been described [27]. The consequence of the mutations is alterations of meiotic divisions leading to tetraploid spermatozoa.