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Mendiola C, Ortega V, Britt A, Fonseca R, Velagaleti G. Double aneuploidy mosaicism involving chromosomes 18 and 21 in a neonate. Mol Cytogenet 2022; 15:1. [PMID: 35073929 PMCID: PMC8785446 DOI: 10.1186/s13039-021-00578-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 11/17/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Double aneuploidy is common, especially in products of conception, frequently involving a combination of a sex chromosome and an acrocentric chromosome. Double autosomal trisomies are rare with only five cases reported. Double aneuploidy mosaicism involving two different cell lines is rarer with only three cases reported. CASE PRESENTATION We report a fourth case of double aneuploidy mosaicism on a baby. Results of a 24-h preliminary chromosome analysis at birth showed a mosaic karyotype, 47,XX,+18[15]/47,XX,+21[8]/48,XX,+21,+mar[7]. Reflex testing to SNP microarray with the same sample collected at birth showed gain of a 77.9 Mb region on chromosome 18 and gain of a 32.5 Mb region on chromosome 21. Microarray did not show any other copy number variants indicating that the marker chromosome may not contain any euchromatic material. A repeat chromosome analysis at 1-year of age showed a mosaic karyotype, 47,XX,+18[76]/47,XX,+21[4] with loss of the marker cell line. CONCLUSION Based on our results, we propose that the mosaic double autosomal trisomy in our case was due to two independent non-disjunction events in a normal zygote very early during embryogenesis.
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Affiliation(s)
- Christina Mendiola
- Department of Pathology and Laboratory Medicine, UT Health -San Antonio, 7703 Floyd Curl Drive, Mail Code 7750, San Antonio, TX, 78229, USA
| | - Veronica Ortega
- Department of Pathology and Laboratory Medicine, UT Health -San Antonio, 7703 Floyd Curl Drive, Mail Code 7750, San Antonio, TX, 78229, USA
| | - Allison Britt
- Department of Pediatrics, University of Texas Medical Branch, Galveston, TX, USA
| | - Rafael Fonseca
- Department of Pediatrics, University of Texas Medical Branch, Galveston, TX, USA
| | - Gopalrao Velagaleti
- Department of Pathology and Laboratory Medicine, UT Health -San Antonio, 7703 Floyd Curl Drive, Mail Code 7750, San Antonio, TX, 78229, USA.
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Hochstenbach R, Liehr T, Hastings RJ. Chromosomes in the genomic age. Preserving cytogenomic competence of diagnostic genome laboratories. Eur J Hum Genet 2021; 29:541-552. [PMID: 33311710 PMCID: PMC8115145 DOI: 10.1038/s41431-020-00780-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 10/26/2020] [Accepted: 11/17/2020] [Indexed: 12/13/2022] Open
Abstract
Participation of clinical genetic laboratories in External Quality Assessment schemes (EQAs) is a powerful method to ascertain if any improvement or additional training is required in the diagnostic service. Here, we provide evidence from recent EQAs that the competence in recognizing and interpreting cytogenetic aberrations is variable and could impact patient management. We identify several trends that could affect cytogenomic competence. Firstly, as a result of the age distribution among clinical laboratory geneticists (CLGs) registered at the European Board of Medical Genetics, about 25-30% of those with experience in cytogenetics will retire during the next decade. At the same time, there are about twice as many molecular geneticists to cytogeneticists among the younger CLGs. Secondly, when surveying training programs for CLG, we observed that not all programs guarantee that candidates gather sufficient experience in clinical cytogenomics. Thirdly, we acknowledge that whole genome sequencing (WGS) has a great attraction to biomedical scientists that wish to enter a training program for CLG. This, with a larger number of positions available, makes a choice for specialization in molecular genetics logical. However, current WGS technology cannot provide a diagnosis in all cases. Understanding the etiology of chromosomal rearrangements is essential for appropriate follow-up and for ascertaining recurrence risks. We define the minimal knowledge a CLG should have about cytogenomics in a world dominated by WGS, and discuss how laboratory directors and boards of professional organizations in clinical genetics can uphold cytogenomic competence by providing adequate CLG training programs and attracting sufficient numbers of trainees.
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Affiliation(s)
- Ron Hochstenbach
- Amsterdam UMC, location Vrije Universiteit Amsterdam, Department of Clinical Genetics, De Boelelaan 1117, 1081, HV, Amsterdam, The Netherlands.
| | - Thomas Liehr
- University Clinic Jena, Institute of Human Genetics, Am Klinikum 1, 07747, Jena, Germany
| | - Rosalind J Hastings
- GenQA, Level 1, The Women's Centre, John Radcliffe Hospital, Oxford University Hospitals Foundation Trust, Headley Way, Headington, Oxford, OX3 9DU, UK
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Al-Rikabi ABH, Pekova S, Fan X, Jančušková T, Liehr T. Small Supernumerary Marker Chromosome May Provide Information on Dosage-insensitive Pericentric Regions in Human. Curr Genomics 2018; 19:192-199. [PMID: 29606906 PMCID: PMC5850507 DOI: 10.2174/1389202918666170717163830] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Revised: 11/18/2016] [Accepted: 01/20/2017] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Cytogenetically visible chromosomal imbalances in humans are deleterious and adverse in the majority of the cases. However, healthy persons living with chromosomal imbalances in the range of several megabasepairs (Mbps) in size, like carriers of small Supernumerary Marker Chromosomes (sSMCs) exist. MATERIALS & METHODS The identification of healthy sSMC carriers with euchromatic centromere-near (ECN) imbalances led to the following proposal: ECN-regions do not contain any dosage sensitive genes. Due to own previous work, dosage-insensitive pericentric ECN-regions were already determined with an accuracy of 0.3 and 5 Mbp. Based on this data we established 43 new pericentromeric probe sets spanning about 3-5 Mbp of each euchromatic human chromosome arm starting from the known insensitive regions towards distal. Such so called pericentromeric-critical region fluorescence in situ hybridization (PeCR-FISH) probe sets were applied exemplarily and successful here in 15 sSMC cases as available from the Else Kröner-Fresenius-sSMC-cellbank . CONCLUSION Most of the involved sSMC breakpoints could be characterized as a higher resolution than before. An unexpected result was that in 5/15 cases cryptic mosaicism was characterized. The latter is also to be considered to have potentially an influence on the clinical outcome in these so-called discontinuous sSMCs. Overall, the suitability of PeCR-FISH to characterize sSMCs was proven; the potential of this probe set to further delineate sizes of dosage insensitive pericentric regions is obvious but dependent on suited cases. Furthermore, discontinuous sSMCs can be identified by this approach and this new subtype of sSMC needs to be studied in more detail in future.
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Affiliation(s)
- Ahmed B. Hamid Al-Rikabi
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Am Klinikum 1, 07747Jena, Germany
| | - Sona Pekova
- Synlab Genetics s.r.o., Evropska 176/16, 16000 Prague 6, Czech Republic
| | - Xioabo Fan
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Am Klinikum 1, 07747Jena, Germany
| | - Tereza Jančušková
- Synlab Genetics s.r.o., Evropska 176/16, 16000 Prague 6, Czech Republic
| | - Thomas Liehr
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Am Klinikum 1, 07747Jena, Germany
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Heng HH, Horne SD, Chaudhry S, Regan SM, Liu G, Abdallah BY, Ye CJ. A Postgenomic Perspective on Molecular Cytogenetics. Curr Genomics 2018; 19:227-239. [PMID: 29606910 PMCID: PMC5850511 DOI: 10.2174/1389202918666170717145716] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 01/29/2017] [Accepted: 02/03/2017] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND The postgenomic era is featured by massive data collection and analyses from various large scale-omics studies. Despite the promising capability of systems biology and bioinformatics to handle large data sets, data interpretation, especially the translation of -omics data into clinical implications, has been challenging. DISCUSSION In this perspective, some important conceptual and technological limitations of current systems biology are discussed in the context of the ultimate importance of the genome beyond the collection of all genes. Following a brief summary of the contributions of molecular cytogenetics/cytogenomics in the pre- and post-genomic eras, new challenges for postgenomic research are discussed. Such discussion leads to a call to search for a new conceptual framework and holistic methodologies. CONCLUSION Throughout this synthesis, the genome theory of somatic cell evolution is highlighted in contrast to gene theory, which ignores the karyotype-mediated higher level of genetic information. Since "system inheritance" is defined by the genome context (gene content and genomic topology) while "parts inheritance" is defined by genes/epigenes, molecular cytogenetics and cytogenomics (which directly study genome structure, function, alteration and evolution) will play important roles in this postgenomic era.
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Affiliation(s)
- Henry H. Heng
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, USA
- Department of Pathology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Steven D. Horne
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, USA
| | - Sophia Chaudhry
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, USA
| | - Sarah M. Regan
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, USA
| | - Guo Liu
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, USA
| | - Batoul Y. Abdallah
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, USA
| | - Christine J. Ye
- The Division of Hematology/Oncology, University of Michigan Comprehensive Cancer Center, Ann Arbor, MI, USA
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5
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Weise A, Bhatt S, Piaszinski K, Kosyakova N, Fan X, Altendorf-Hofmann A, Tanomtong A, Chaveerach A, de Cioffi MB, de Oliveira E, Walther JU, Liehr T, Chaudhuri JP. Chromosomes in a genome-wise order: evidence for metaphase architecture. Mol Cytogenet 2016; 9:36. [PMID: 27123045 PMCID: PMC4847357 DOI: 10.1186/s13039-016-0243-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 04/12/2016] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND One fundamental finding of the last decade is that, besides the primary DNA sequence information there are several epigenetic "information-layers" like DNA-and histone modifications, chromatin packaging and, last but not least, the position of genes in the nucleus. RESULTS We postulate that the functional genomic architecture is not restricted to the interphase of the cell cycle but can also be observed in the metaphase stage, when chromosomes are most condensed and microscopically visible. If so, it offers the unique opportunity to directly analyze the functional aspects of genomic architecture in different cells, species and diseases. Another aspect not directly accessible by molecular techniques is the genome merged from two different haploid parental genomes represented by the homologous chromosome sets. Our results show that there is not only a well-known and defined nuclear architecture in interphase but also in metaphase leading to a bilateral organization of the two haploid sets of chromosomes. Moreover, evidence is provided for the parental origin of the haploid grouping. CONCLUSIONS From our findings we postulate an additional epigenetic information layer within the genome including the organization of homologous chromosomes and their parental origin which may now substantially change the landscape of genetics.
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Affiliation(s)
- Anja Weise
- />Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany
| | - Samarth Bhatt
- />Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany
| | - Katja Piaszinski
- />Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany
| | - Nadezda Kosyakova
- />Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany
| | - Xiaobo Fan
- />Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany
| | - Annelore Altendorf-Hofmann
- />Department of General, Visceral und Vascular Surgery, Jena University Hospital, Kochstr. 2, Jena, 07743 Germany
| | - Alongklod Tanomtong
- />Department of Biology, Faculty of Science, Khon Kaen University, 123 Moo 16 Mittapap Rd, Khon Kaen, Muang District 40002 Thailand
| | - Arunrat Chaveerach
- />Department of Biology, Faculty of Science, Khon Kaen University, 123 Moo 16 Mittapap Rd, Khon Kaen, Muang District 40002 Thailand
| | - Marcelo Bello de Cioffi
- />Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, SP Brazil
| | - Edivaldo de Oliveira
- />Instituto Evandro Chagas, Seção de Meio Ambiente, Laboratório de Cultura de Tecidos e Citogenética, Ananindeua, PA Brazil
| | - Joachim-U. Walther
- />Instituto Evandro Chagas, Seção de Meio Ambiente, Laboratório de Cultura de Tecidos e Citogenética, Ananindeua, PA Brazil
| | - Thomas Liehr
- />Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany
| | - Jyoti P. Chaudhuri
- />Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany
- />Kinderklinik, Ludwig Maximillians Universität, 80337 Munich, Germany
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Poot M. From Telomere Crisis via Dicentric Chromosomes to Kataegis and Chromothripsis. Mol Syndromol 2016; 6:259-60. [PMID: 27022325 DOI: 10.1159/000443805] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/30/2015] [Indexed: 11/19/2022] Open
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Hochstenbach R, Nowakowska B, Volleth M, Ummels A, Kutkowska-Kaźmierczak A, Obersztyn E, Ziemkiewicz K, Gerloff C, Schanze D, Zenker M, Muschke P, Schanze I, Poot M, Liehr T. Multiple Small Supernumerary Marker Chromosomes Resulting from Maternal Meiosis I or II Errors. Mol Syndromol 2016; 6:210-21. [PMID: 26997941 PMCID: PMC4772618 DOI: 10.1159/000441408] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/16/2015] [Indexed: 01/11/2023] Open
Abstract
We present 2 cases with multiple de novo supernumerary marker chromosomes (sSMCs), each derived from a different chromosome. In a prenatal case, we found mosaicism for an sSMC(4), sSMC(6), sSMC(9), sSMC(14) and sSMC(22), while a postnatal case had an sSMC(4), sSMC(8) and an sSMC(11). SNP-marker segregation indicated that the sSMC(4) resulted from a maternal meiosis II error in the prenatal case. Segregation of short tandem repeat markers on the sSMC(8) was consistent with a maternal meiosis I error in the postnatal case. In the latter, a boy with developmental/psychomotor delay, autism, hyperactivity, speech delay, and hypotonia, the sSMC(8) was present at the highest frequency in blood. By comparison to other patients with a corresponding duplication, a minimal region of overlap for the phenotype was identified, with CHRNB3 and CHRNA6 as dosage-sensitive candidate genes. These genes encode subunits of nicotinic acetylcholine receptors (nAChRs). We propose that overproduction of these subunits leads to perturbed component stoichiometries with dominant negative effects on the function of nAChRs, as was shown by others in vitro. With the limitation that in each case only one sSMC could be studied, our findings demonstrate that different meiotic errors lead to multiple sSMCs. We relate our findings to age-related aneuploidy in female meiosis and propose that predivision sister-chromatid separation during meiosis I or II, or both, may generate multiple sSMCs.
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Affiliation(s)
- Ron Hochstenbach
- Division of Biomedical Genetics, Department of Medical Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Beata Nowakowska
- Department of Medical Genetics, Institute of the Mother and Child, Warsaw, Poland
| | | | - Amber Ummels
- Division of Biomedical Genetics, Department of Medical Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Ewa Obersztyn
- Department of Medical Genetics, Institute of the Mother and Child, Warsaw, Poland
| | - Kamila Ziemkiewicz
- Department of Medical Genetics, Institute of the Mother and Child, Warsaw, Poland
| | - Claudia Gerloff
- University Women's Clinic, Otto-von-Guericke University, Magdeburg, Germany
| | | | | | | | - Ina Schanze
- Department of Human Genetics, Magdeburg, Germany
| | - Martin Poot
- Division of Biomedical Genetics, Department of Medical Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Thomas Liehr
- Department of Human Genetics, University Clinic, Jena, Germany
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Pérez-Roca F, Rodrigo-Morales E, Garzón I, Oliveira AC, Martín-Piedra MÁ, Carriel V, Ortiz-Pérez AI, Sánchez-Montesinos I, Campos A, Alaminos M. Effects of Four Formulations of Prostaglandin Analogs on Eye Surface Cells. A Comparative Study. PLoS One 2015; 10:e0129419. [PMID: 26067827 PMCID: PMC4466352 DOI: 10.1371/journal.pone.0129419] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2015] [Accepted: 04/23/2015] [Indexed: 01/18/2023] Open
Abstract
We evaluated the cytotoxic effects of four prostaglandin analogs (PGAs) used to treat glaucoma. First we established primary cultures of conjunctival stromal cells from healthy donors. Then cell cultures were incubated with different concentrations (0, 0.1, 1, 5, 25, 50 and 100%) of commercial formulations of bimatoprost, tafluprost, travoprost and latanoprost for increasing periods (5 and 30 min, 1 h, 6 h and 24 h) and cell survival was assessed with three different methods: WST-1, MTT and calcein/AM-ethidium homodimer-1 assays. Our results showed that all PGAs were associated with a certain level of cell damage, which correlated significantly with the concentration of PGA used, and to a lesser extent with culture time. Tafluprost tended to be less toxic than bimatoprost, travoprost and latanoprost after all culture periods. The results for WST-1, MTT and calcein/AM-ethidium homodimer-1 correlated closely. When the average lethal dose 50 was calculated, we found that the most cytotoxic drug was latanoprost, whereas tafluprost was the most sparing of the ocular surface in vitro. These results indicate the need to design novel PGAs with high effectiveness but free from the cytotoxic effects that we found, or at least to obtain drugs that are functional at low dosages. The fact that the commercial formulation of tafluprost used in this work was preservative-free may support the current tendency to eliminate preservatives from eye drops for clinical use.
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Affiliation(s)
- Fernando Pérez-Roca
- Hospital General Básico de Baza, E18800, Granada, Spain
- PhD Program in Biomedicine, University of Granada, 18012, Granada, Spain
| | | | - Ingrid Garzón
- Tissue Engineering Group, Department of Histology, University of Granada, 18012, Granada, Spain
- Instituto de Investigación Biosanitaria ibs.GRANADA, 18012, Granada, Spain
| | - Ana-Celeste Oliveira
- Tissue Engineering Group, Department of Histology, University of Granada, 18012, Granada, Spain
| | - Miguel-Ángel Martín-Piedra
- Tissue Engineering Group, Department of Histology, University of Granada, 18012, Granada, Spain
- Instituto de Investigación Biosanitaria ibs.GRANADA, 18012, Granada, Spain
| | - Víctor Carriel
- Tissue Engineering Group, Department of Histology, University of Granada, 18012, Granada, Spain
- Instituto de Investigación Biosanitaria ibs.GRANADA, 18012, Granada, Spain
| | | | | | - Antonio Campos
- Tissue Engineering Group, Department of Histology, University of Granada, 18012, Granada, Spain
- Instituto de Investigación Biosanitaria ibs.GRANADA, 18012, Granada, Spain
| | - Miguel Alaminos
- Tissue Engineering Group, Department of Histology, University of Granada, 18012, Granada, Spain
- Instituto de Investigación Biosanitaria ibs.GRANADA, 18012, Granada, Spain
- * E-mail:
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Pota P, Grammatopoulou V, Torti E, Braddock S, Batanian JR. Instability of isochromosome 4p in a child with pure trisomy 4p syndrome features and entire 4q-arm translocation. Cytogenet Genome Res 2015; 144:280-4. [PMID: 25632983 DOI: 10.1159/000371606] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/20/2014] [Indexed: 11/19/2022] Open
Abstract
Constitutional chromosome instability so far has mainly been associated with ring formation. In addition, isochromosome formation involving the short arm with translocation of the entire long arm is rarely observed. This type of rearrangement has been reported for chromosomes 4, 5, 7, 9, 10, 12, and 20. Here, we present the third patient having an isochromosome 4p with 4q translocation, but showing for the first time chromosome instability detected by FISH following chromosome microarray analysis.
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Affiliation(s)
- Pruthvi Pota
- Departments of Pediatrics and Molecular Cytogenetics, SSM Cardinal Glennon Children's and Saint Louis University Medical Centers, Saint Louis, Mo., USA
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Hussein SS, Kreskowski K, Ziegler M, Klein E, Hamid AB, Kosyakova N, Volleth M, Liehr T, Fan X, Piaszinski K. Mitotic stability of small supernumerary marker chromosomes depends on their shape and telomeres - a long term in vitro study. Gene 2014; 552:246-8. [PMID: 25245454 DOI: 10.1016/j.gene.2014.09.041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 09/19/2014] [Indexed: 12/23/2022]
Abstract
Mosaicism is present in more than 50% of the cases with small supernumerary marker chromosomes (sSMCs) and karyotype 47,XX,+mar/46,XX or 47,XY,+mar/46,XY. Recently we provided first evidence that the mitotic stability of sSMC is dependent on their structure, i.e. their shape. Thus, here we performed a long term in vitro study on 12 selected cell lines from the Else Kröner-Fresenius-sSMC-cellbank (http://ssmc-tl.com/ekf-cellbank.html) to test mitotic sSMC stability systematically. The obtained results showed that inverted duplicated shaped and also the so-called complex sSMCs (group 1) are by far more stable, than centric-minute- or ring-shaped sSMCs (groups 2). Generally speaking, the percentage of cells with group-1-sSMCs remained stable over 90 days of cell culture, while that of group-2-sSMCs in parts dramatically decreased. In one group-2-cell line the sSMC was even lost completely after 30 days of in vitro culture, in others the sSMC was depleted in up to 40% of the cells. Still the highest rate of sSMC loss was recorded during EBV-transformation. Overall, the major difference between groups 1 and 2 was the number of telomeres per sSMC. In group 1 the sSMCs had "original" telomeres at both of their ends; in group 2 the sSMCs had either no, possibly secondary acquired and/or only one original telomere. This absence of protective telomeric sequences in group 2 seems to make sSMC more susceptible for loss during cell division. Still, also a growth advantage of cells without sSMC cannot be neglected entirely.
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Affiliation(s)
- Shaymaa Subhi Hussein
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Kollegiengasse 10, D-07743 Jena, Germany
| | - Katharina Kreskowski
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Kollegiengasse 10, D-07743 Jena, Germany
| | - Monika Ziegler
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Kollegiengasse 10, D-07743 Jena, Germany
| | - Elisabeth Klein
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Kollegiengasse 10, D-07743 Jena, Germany
| | - Ahmed B Hamid
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Kollegiengasse 10, D-07743 Jena, Germany
| | - Nadezda Kosyakova
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Kollegiengasse 10, D-07743 Jena, Germany
| | - Marianne Volleth
- Institut für Humangenetik, Universitätsklinikum, Leipziger Str. 44, 39120 Magdeburg, Germany
| | - Thomas Liehr
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Kollegiengasse 10, D-07743 Jena, Germany.
| | - Xiaobo Fan
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Kollegiengasse 10, D-07743 Jena, Germany
| | - Katja Piaszinski
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Kollegiengasse 10, D-07743 Jena, Germany
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