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Seixas J, Padutsch N, Kankel S, Liehr T, Sy A. Molecular Cytogenetic Characterization of Rare but Repeatedly Observed Inversions in German Population. Cytogenet Genome Res 2024:1-7. [PMID: 38797165 DOI: 10.1159/000539447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Accepted: 05/21/2024] [Indexed: 05/29/2024] Open
Abstract
INTRODUCTION The term inversion refers to an aberration caused by two breakage and fusion events found in one or both arms of a chromosome. The presence of such aberrations can but must not be associated with infertility or unbalanced products of conception. Normally, inversions are not associated with phenotypic alterations for the carrier. Despite the fact that most such inversions are de novo and unique, recurrent breakpoints have also been reported. METHODS Here two recurrent paracentric inversions in the long arm of chromosomes 11 and 12 and a pericentric one in chromosome 10 were studied in at least 10 unrelated (infertile) patients, each. Breakpoints were narrowed down by fluorescence in situ hybridization applying locus-specific bacterial artificial chromosome-derived probes. RESULTS Molecular cytogenetically identical breakpoints could be characterized for all three studied inversions. Pericentric inversion inv(10)(p11.21q21.2), previously reported to be of single origin and distributed mainly in Northern Europe, could be found to be present all over Germany, too. In the studied cases with paracentric inversion inv(11)(q21q23.3), recurrent breakpoints were found in all parts of Germany, as well; however, additional 2 cases with slightly different breakpoints were characterized besides. Most interestingly, inversion inv(12)(q14.1∼14.2q24.11∼24.13) had always the same recurrent breakpoints and presented an exclusive occurrence in North-Western part of Germany. CONCLUSION Overall, (at least) three different cytogenetically detectable recurrent inversions were characterized here. This highlights that such events may be more frequent in human population than yet suggested. Accordingly, such events might even spread in (middle European) human population. Specific impact on reproduction and fitness of inversion carriers characterized here seems to be negligible. Nonetheless, such recurrent rearrangements need more attention as they may provide valuable information for genetic counseling in future.
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Affiliation(s)
- Joana Seixas
- Jena University Hospital, Institute of Human Genetics, Friedrich Schiller University, Jena, Germany
- Coimbra University, Faculty of Medicine, Coimbra, Portugal
| | - Niklas Padutsch
- Jena University Hospital, Institute of Human Genetics, Friedrich Schiller University, Jena, Germany
| | - Stefanie Kankel
- Jena University Hospital, Institute of Human Genetics, Friedrich Schiller University, Jena, Germany
| | - Thomas Liehr
- Jena University Hospital, Institute of Human Genetics, Friedrich Schiller University, Jena, Germany
| | - Alody Sy
- Jena University Hospital, Institute of Human Genetics, Friedrich Schiller University, Jena, Germany
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2
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Kosuthova K, Solc R. Inversions on human chromosomes. Am J Med Genet A 2023; 191:672-683. [PMID: 36495134 DOI: 10.1002/ajmg.a.63063] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 11/13/2022] [Accepted: 11/17/2022] [Indexed: 12/14/2022]
Abstract
Human chromosome inversions are types of balanced structural variations, making them difficult to analyze. Thanks to PEM (paired-end sequencing and mapping), there has been tremendous progress in studying inversions. Inversions play an important role as an evolutionary factor, contributing to the formation of gonosomes, speciation of chimpanzees and humans, and inv17q21.3 or inv8p23.1 exhibit the features of natural selection. Both inversions have been related to pathogenic phenotype by directly affecting a gene structure (e.g., inv5p15.1q14.1), regulating gene expression (e.g., inv7q21.3q35) and by predisposing to other secondary arrangements (e.g., inv7q11.23). A polymorphism of human inversions is documented by the InvFEST database (a database that stores information about clinical predictions, validations, frequency of inversions, etc.), but only a small fraction of these inversions is validated, and a detailed analysis is complicated by the frequent location of breakpoints within regions of repetitive sequences.
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Affiliation(s)
- Klara Kosuthova
- Department of Anthropology and Human Genetics, Faculty of Science, Charles University, Prague, Czech Republic
| | - Roman Solc
- Department of Anthropology and Human Genetics, Faculty of Science, Charles University, Prague, Czech Republic
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3
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Zhang X, Shi Q, Liu Y, Jiang Y, Yang X, Liu R, Zhang H. Fertility problems in males carrying an inversion of chromosome 10. Open Med (Wars) 2021; 16:316-321. [PMID: 33681470 PMCID: PMC7917366 DOI: 10.1515/med-2021-0240] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 12/15/2020] [Accepted: 01/21/2021] [Indexed: 12/14/2022] Open
Abstract
Chromosomal inversion is closely related to male infertility. Inversion carriers may produce abnormal gametes, which may lead to partial duplication/deletion of the embryonic chromosome and result in spontaneous abortion, a fetus with multiple anomalies, or birth of a malformed child. Genetic counselling remains challenging for these carriers in clinical practice. We report two male carriers with inversion of chromosome 10 and review 26 reported cases. In the first case, 46,XX,inv(10)(p13q22) of the fetal chromosome was found in prenatal diagnosis; this was inherited from the paternal side with 46XY,inv(10)(p13q22). Another case was a male carrier with inv(10)(q21.2q22.1). There have been 25 (89.3%) cases of pericentric inversion and three (10.7%) cases of paracentric inversion involving chromosome 10. Of 28 cases, nine were associated with pregestational infertility of the couples, while the other 19 cases were associated with gestational infertility of the couples or normozoospermia. The breakpoints at 10p15, 10p11, 10q11, and 10q21 were associated with pregestational infertility of the couples. The breakpoints at 10p15, 10p14, 10p13, 10p12, 10p11, 10q11, 10q21, 10q22, 10q23, 10q24, 10q25, and 10q26 were related to gestational infertility of the couples or normozoospermia. Although there is a high risk of infertility or recurrent miscarriages, carriers with inversion of chromosome 10 might produce healthy offspring. Natural pregnancy can be used as a choice for inversion carriers with recurrent spontaneous abortion.
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Affiliation(s)
- Xinyue Zhang
- Center for Reproductive Medicine and Center for Prenatal Diagnosis, First Hospital, Jilin University, 1 Xinmin Street, Chaoyang District, Changchun, Jilin Province, 130021, China
| | - Qingyang Shi
- Center for Reproductive Medicine and Center for Prenatal Diagnosis, First Hospital, Jilin University, 1 Xinmin Street, Chaoyang District, Changchun, Jilin Province, 130021, China
| | - Yanhong Liu
- Center for Reproductive Medicine and Center for Prenatal Diagnosis, First Hospital, Jilin University, 1 Xinmin Street, Chaoyang District, Changchun, Jilin Province, 130021, China
| | - Yuting Jiang
- Center for Reproductive Medicine and Center for Prenatal Diagnosis, First Hospital, Jilin University, 1 Xinmin Street, Chaoyang District, Changchun, Jilin Province, 130021, China
| | - Xiao Yang
- Center for Reproductive Medicine and Center for Prenatal Diagnosis, First Hospital, Jilin University, 1 Xinmin Street, Chaoyang District, Changchun, Jilin Province, 130021, China
| | - Ruizhi Liu
- Center for Reproductive Medicine and Center for Prenatal Diagnosis, First Hospital, Jilin University, 1 Xinmin Street, Chaoyang District, Changchun, Jilin Province, 130021, China
| | - Hongguo Zhang
- Center for Reproductive Medicine and Center for Prenatal Diagnosis, First Hospital, Jilin University, 1 Xinmin Street, Chaoyang District, Changchun, Jilin Province, 130021, China
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Pettersson M, Grochowski CM, Wincent J, Eisfeldt J, Breman AM, Cheung SW, Krepischi ACV, Rosenberg C, Lupski JR, Ottosson J, Lovmar L, Gacic J, Lundberg ES, Nilsson D, Carvalho CMB, Lindstrand A. Cytogenetically visible inversions are formed by multiple molecular mechanisms. Hum Mutat 2020; 41:1979-1998. [PMID: 32906200 PMCID: PMC7702065 DOI: 10.1002/humu.24106] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 08/10/2020] [Accepted: 08/28/2020] [Indexed: 01/25/2023]
Abstract
Cytogenetically detected inversions are generally assumed to be copy number and phenotypically neutral events. While nonallelic homologous recombination is thought to play a major role, recent data suggest the involvement of other molecular mechanisms in inversion formation. Using a combination of short-read whole-genome sequencing (WGS), 10X Genomics Chromium WGS, droplet digital polymerase chain reaction and array comparative genomic hybridization we investigated the genomic structure of 18 large unique cytogenetically detected chromosomal inversions and achieved nucleotide resolution of at least one chromosomal inversion junction for 13/18 (72%). Surprisingly, we observed that seemingly copy number neutral inversions can be accompanied by a copy-number gain of up to 350 kb and local genomic complexities (3/18, 17%). In the resolved inversions, the mutational signatures are consistent with nonhomologous end-joining (8/13, 62%) or microhomology-mediated break-induced replication (5/13, 38%). Our study indicates that short-read 30x coverage WGS can detect a substantial fraction of chromosomal inversions. Moreover, replication-based mechanisms are responsible for approximately 38% of those events leading to a significant proportion of inversions that are actually accompanied by additional copy-number variation potentially contributing to the overall phenotypic presentation of those patients.
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Affiliation(s)
- Maria Pettersson
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
| | | | - Josephine Wincent
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
| | - Jesper Eisfeldt
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Science for Life Laboratory, Karolinska Institutet, Solna, Sweden
| | - Amy M Breman
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Sau W Cheung
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Ana C V Krepischi
- Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Carla Rosenberg
- Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, USA.,Department of Pediatrics, Texas Children's Hospital, Houston, Texas, USA
| | - Jesper Ottosson
- Department of Clinical Genetics, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Lovisa Lovmar
- Department of Clinical Genetics, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Jelena Gacic
- Department of Clinical Genetics, Linköping University Hospital, Linköping, Sweden
| | - Elisabeth S Lundberg
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
| | - Daniel Nilsson
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden.,Science for Life Laboratory, Karolinska Institutet, Solna, Sweden
| | - Claudia M B Carvalho
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Pacific Northwest Research Institute, Seattle, Washington, USA
| | - Anna Lindstrand
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
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Follow-up of two adult brothers with homozygous CEP57 pathogenic variants expands the phenotype of Mosaic Variegated Aneuploidy Syndrome. Eur J Med Genet 2020; 63:104044. [PMID: 32861809 DOI: 10.1016/j.ejmg.2020.104044] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 07/15/2020] [Accepted: 08/20/2020] [Indexed: 11/23/2022]
Abstract
Mosaic Variegated Aneuploidy Syndrome (MVA) is a rare autosomal recessive disorder characterized by mosaic aneuploidies involving multiple chromosomes and tissues. Affected individuals typically present with severe intrauterine and postnatal growth retardation, microcephaly, facial dysmorphism, developmental delay and predisposition to cancer and epilepsy. Three genes, BUB1B, CEP57 and TRIP13, are involved in this syndrome. Only 7 patients carrying pathogenic variants in CEP57 are reported to date. Here we report two adult brothers born to Moroccan related parents, who presented with intrauterine and postnatal growth retardation, microcephaly, facial dysmorphism, learning disabilities, skeletal anomalies with thumb hypoplasia and dental abnormalities. Both brothers have mosaic variegated aneuploidies on blood karyotype. A previously reported homozygous 11 bp duplication was identified in CEP57 in the two brothers. We propose that a FoSTeS (Fork Stalling and Template Switching) mechanism could be involved in the occurrence of this duplication. This report expands the phenotypical spectrum associated with CEP57 and highlights the interest of blood karyotype in patients presenting with short stature and microcephaly.
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6
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Sismani C, Rapti SM, Iliopoulou P, Spring A, Neroutsou R, Lagou M, Robola M, Tsitsopoulos E, Kousoulidou L, Alexandrou A, Papaevripidou I, Theodosiou A, Syrrou M, Fuchs S, Hempel M, Huhle D, Liehr T, Ziegler M, Duesberg M, Velissariou V. Novel pericentric inversion inv(9)(p23q22.3) in unrelated individuals with fertility problems in the Southeast European population. J Hum Genet 2020; 65:783-795. [PMID: 32398760 DOI: 10.1038/s10038-020-0769-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 04/25/2020] [Accepted: 04/27/2020] [Indexed: 11/09/2022]
Abstract
Pericentric inversions are among the known polymorphisms detected in the general population at a frequency of 1-2%. Despite their generally benign nature, pericentric inversions affect the reproductive potential of carriers by increasing the risk for unbalanced live-born offspring, miscarriages, or other fertility problems. Here we present a novel large pericentric inversion of chromosome 9, inv(9)(p23q22.3), detected in 30 heterozygote carriers, 24 from seven apparently unrelated families and 6 isolated patients, where the probands were mainly referred for fertility and prenatal problems. The inversion carries a significant risk for recombinant abnormal chromosomes, as in two families one supernumerary rec(9)dup(9p) and one rec(9)dup(9q) were identified, leading to neonatal death and miscarriage, respectively. The inversion carriers were identified by three different laboratories in Greece, Cyprus and Germany respectively, however all carriers have Southeast European origin. The inversion appears to be more frequent in the Greek population, as the majority of the carriers were identified in Greece. We were able to determine that the inversion is identical in all individuals included in the study by applying a combination of several methodologies, such as karyotype, fluorescence in situ hybridization (FISH), chromosomal microarrays (CMA) and haplotype analysis. In addition, haplotype analysis supports that the present inversion is identical by descent (IBD) inherited from a single common ancestor. Our results are, therefore, highly indicative of a founder effect of this inversion, presumably reflecting an event that was present in a small number of individuals that migrated to the current Southeast Europe/Northern Greece from a larger population.
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Affiliation(s)
- Carolina Sismani
- Department of Cytogenetics and Genomics, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus.,The Cyprus School of Molecular Medicine, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Stamatia-Maria Rapti
- Department of Genetics and Molecular Biology, Bioiatriki Healthcare Group, Athens, Greece
| | - Pavlina Iliopoulou
- Department of Genetics and Molecular Biology, Bioiatriki Healthcare Group, Athens, Greece
| | - Anastasia Spring
- Department of Genetics and Molecular Biology, Bioiatriki Healthcare Group, Athens, Greece
| | - Rozalia Neroutsou
- Department of Genetics and Molecular Biology, Bioiatriki Healthcare Group, Athens, Greece
| | - Magdalini Lagou
- Department of Genetics and Molecular Biology, Bioiatriki Healthcare Group, Athens, Greece
| | - Marianna Robola
- Department of Genetics and Molecular Biology, Bioiatriki Healthcare Group, Athens, Greece
| | | | - Ludmila Kousoulidou
- Department of Cytogenetics and Genomics, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Angelos Alexandrou
- Department of Cytogenetics and Genomics, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Ioannis Papaevripidou
- Department of Cytogenetics and Genomics, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Athina Theodosiou
- Department of Cytogenetics and Genomics, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Maria Syrrou
- Department of Biology, Medical School, University of Ioannina, Ioannina, Greece
| | - Sigrid Fuchs
- Institute of Human Genetics, University Hospital, Hamburg- Eppendorf, Martinistraße 52, D-20246, Hamburg, Germany
| | - Maja Hempel
- Institute of Human Genetics, University Hospital, Hamburg- Eppendorf, Martinistraße 52, D-20246, Hamburg, Germany
| | - Dagmar Huhle
- Medizinisches Versorgungszentrum, Karl- Liebknecht- Str. 14, 04107, Leipzig, Germany
| | - Thomas Liehr
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Am Klinikum 1, D-07747, Jena, Germany
| | - Monika Ziegler
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Am Klinikum 1, D-07747, Jena, Germany
| | - Max Duesberg
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Am Klinikum 1, D-07747, Jena, Germany
| | - Voula Velissariou
- Department of Genetics and Molecular Biology, Bioiatriki Healthcare Group, Athens, Greece. .,NIPD Genetics Public Company Ltd, 31 Neas Engomis Street, 2409, Engomi, Nicosia, Cyprus.
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Drabova J, Trkova M, Hancarova M, Novotna D, Hejtmankova M, Havlovicova M, Sedlacek Z. A 15 Mb large paracentric chromosome 21 inversion identified in Czech population through a pair of flanking duplications. Mol Cytogenet 2014; 7:51. [PMID: 25411581 PMCID: PMC4236861 DOI: 10.1186/1755-8166-7-51] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 06/20/2014] [Indexed: 11/22/2022] Open
Abstract
Background Inversions are balanced structural chromosome rearrangements, which can influence gene expression and the risk of unbalanced chromosome constitution in offspring. Many examples of inversion polymorphisms exist in human, affecting both heterochromatic regions and euchromatin. Results We describe a novel, 15 Mb long paracentric inversion, inv(21)(q21.1q22.11), affecting more than a third of human 21q. Despite of its length, the inversion cannot be detected using karyotyping due to similar band patterns on the normal and inverted chromosomes, and is therefore likely to escape attention. Its identification was aided by the repeated observation of the same pair of 150 kb long duplications present in cis on chromosome 21 in three Czech families subjected to microarray analysis. The finding prompted us to hypothesise that this co-occurrence of two remote duplications could be associated with an inversion of the intervening segment, and this speculation turned out to be right. The inversion was confirmed in a series of FISH experiments which also showed that the second copy of each of the duplications was always located at the opposite end of the inversion. The presence of the same pair of duplications in additional individuals reported in public databases indicates that the inversion may also be present in other populations. Three out of the total of about 4000 chromosomes 21 examined in our sample carried the duplications and were inverted, corresponding to carrier frequency of about 1/660. Although the breakpoints affect protein-coding genes, the occurrence of the inversion in normal parents and siblings of our patients and the occurrence of the duplications in unaffected controls in databases indicate that this rare variant is rather non-pathogenic. The inverted segment carried an identical shared haplotype in the three families studied. The haplotypes, however, diverged very rapidly in the flanking regions, possibly pointing to an ancient founder event at the origin of the inversion. Conclusions The identification of inv(21)(q21.1q22.11) supports the notion that paracentric inversions are the most common form of chromosomal variation and that some of them may still remain undetected.
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Affiliation(s)
- Jana Drabova
- Department of Biology and Medical Genetics, Charles University 2nd Faculty of Medicine and University Hospital Motol, Prague, Czech Republic
| | | | - Miroslava Hancarova
- Department of Biology and Medical Genetics, Charles University 2nd Faculty of Medicine and University Hospital Motol, Prague, Czech Republic
| | - Drahuse Novotna
- Department of Biology and Medical Genetics, Charles University 2nd Faculty of Medicine and University Hospital Motol, Prague, Czech Republic
| | | | - Marketa Havlovicova
- Department of Biology and Medical Genetics, Charles University 2nd Faculty of Medicine and University Hospital Motol, Prague, Czech Republic
| | - Zdenek Sedlacek
- Department of Biology and Medical Genetics, Charles University 2nd Faculty of Medicine and University Hospital Motol, Prague, Czech Republic
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8
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Minocherhomji S, Hansen C, Kim HG, Mang Y, Bak M, Guldberg P, Papadopoulos N, Eiberg H, Doh GD, Møllgård K, Hertz JM, Nielsen JE, Ropers HH, Tümer Z, Tommerup N, Kalscheuer VM, Silahtaroglu A. Epigenetic remodelling and dysregulation of DLGAP4 is linked with early-onset cerebellar ataxia. Hum Mol Genet 2014; 23:6163-76. [PMID: 24986922 PMCID: PMC4222360 DOI: 10.1093/hmg/ddu337] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Genome instability, epigenetic remodelling and structural chromosomal rearrangements are hallmarks of cancer. However, the coordinated epigenetic effects of constitutional chromosomal rearrangements that disrupt genes associated with congenital neurodevelopmental diseases are poorly understood. To understand the genetic-epigenetic interplay at breakpoints of chromosomal translocations disrupting CG-rich loci, we quantified epigenetic modifications at DLGAP4 (SAPAP4), a key post-synaptic density 95 (PSD95) associated gene, truncated by the chromosome translocation t(8;20)(p12;q11.23), co-segregating with cerebellar ataxia in a five-generation family. We report significant epigenetic remodelling of the DLGAP4 locus triggered by the t(8;20)(p12;q11.23) translocation and leading to dysregulation of DLGAP4 expression in affected carriers. Disruption of DLGAP4 results in monoallelic hypermethylation of the truncated DLGAP4 promoter CpG island. This induced hypermethylation is maintained in somatic cells of carriers across several generations in a t(8;20) dependent-manner however, is erased in the germ cells of the translocation carriers. Subsequently, chromatin remodelling of the locus-perturbed monoallelic expression of DLGAP4 mRNAs and non-coding RNAs in haploid cells having the translocation. Our results provide new mechanistic insight into the way a balanced chromosomal rearrangement associated with a neurodevelopmental disorder perturbs allele-specific epigenetic mechanisms at breakpoints leading to the deregulation of the truncated locus.
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Affiliation(s)
- Sheroy Minocherhomji
- Wilhelm Johannsen Centre for Functional Genome Research, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen N DK-2200, Denmark
| | - Claus Hansen
- Wilhelm Johannsen Centre for Functional Genome Research, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen N DK-2200, Denmark
| | - Hyung-Goo Kim
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin 14195, Germany
| | - Yuan Mang
- Wilhelm Johannsen Centre for Functional Genome Research, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen N DK-2200, Denmark
| | - Mads Bak
- Wilhelm Johannsen Centre for Functional Genome Research, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen N DK-2200, Denmark
| | - Per Guldberg
- Danish Cancer Society, Institute of Cancer Biology, Copenhagen DK-2100, Denmark
| | - Nickolas Papadopoulos
- Ludwig Center for Cancer Genetics, Johns Hopkins Kimmel Cancer Center, Baltimore, MD 21231, USA
| | - Hans Eiberg
- Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen N DK-2200, Denmark
| | - Gerald Dayebga Doh
- Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen N DK-2200, Denmark
| | - Kjeld Møllgård
- Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen N DK-2200, Denmark
| | - Jens Michael Hertz
- Department of Clinical Genetics, Odense University Hospital, Odense C DK-5000, Denmark
| | - Jørgen E Nielsen
- Section for Neurogenetics, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen N 2200, Denmark, Danish Dementia Research Centre, Neurogenetics Clinic, Department of Neurology, Rigshospitalet, Copenhagen University Hospital, Copenhagen Ø 2100, Denmark and
| | - Hans-Hilger Ropers
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin 14195, Germany
| | - Zeynep Tümer
- Wilhelm Johannsen Centre for Functional Genome Research, Applied Human Molecular Genetics, Kennedy Center, Copenhagen University Hospital, Rigshospitalet, Glostrup DK-2600, Denmark
| | - Niels Tommerup
- Wilhelm Johannsen Centre for Functional Genome Research, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen N DK-2200, Denmark
| | - Vera M Kalscheuer
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin 14195, Germany
| | - Asli Silahtaroglu
- Wilhelm Johannsen Centre for Functional Genome Research, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen N DK-2200, Denmark,
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9
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Aguado C, Gayà-Vidal M, Villatoro S, Oliva M, Izquierdo D, Giner-Delgado C, Montalvo V, García-González J, Martínez-Fundichely A, Capilla L, Ruiz-Herrera A, Estivill X, Puig M, Cáceres M. Validation and genotyping of multiple human polymorphic inversions mediated by inverted repeats reveals a high degree of recurrence. PLoS Genet 2014; 10:e1004208. [PMID: 24651690 PMCID: PMC3961182 DOI: 10.1371/journal.pgen.1004208] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 01/14/2014] [Indexed: 01/17/2023] Open
Abstract
In recent years different types of structural variants (SVs) have been discovered in the human genome and their functional impact has become increasingly clear. Inversions, however, are poorly characterized and more difficult to study, especially those mediated by inverted repeats or segmental duplications. Here, we describe the results of a simple and fast inverse PCR (iPCR) protocol for high-throughput genotyping of a wide variety of inversions using a small amount of DNA. In particular, we analyzed 22 inversions predicted in humans ranging from 5.1 kb to 226 kb and mediated by inverted repeat sequences of 1.6-24 kb. First, we validated 17 of the 22 inversions in a panel of nine HapMap individuals from different populations, and we genotyped them in 68 additional individuals of European origin, with correct genetic transmission in ∼ 12 mother-father-child trios. Global inversion minor allele frequency varied between 1% and 49% and inversion genotypes were consistent with Hardy-Weinberg equilibrium. By analyzing the nucleotide variation and the haplotypes in these regions, we found that only four inversions have linked tag-SNPs and that in many cases there are multiple shared SNPs between standard and inverted chromosomes, suggesting an unexpected high degree of inversion recurrence during human evolution. iPCR was also used to check 16 of these inversions in four chimpanzees and two gorillas, and 10 showed both orientations either within or between species, providing additional support for their multiple origin. Finally, we have identified several inversions that include genes in the inverted or breakpoint regions, and at least one disrupts a potential coding gene. Thus, these results represent a significant advance in our understanding of inversion polymorphism in human populations and challenge the common view of a single origin of inversions, with important implications for inversion analysis in SNP-based studies.
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Affiliation(s)
- Cristina Aguado
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
| | - Magdalena Gayà-Vidal
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
| | - Sergi Villatoro
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
| | - Meritxell Oliva
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
| | - David Izquierdo
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
| | - Carla Giner-Delgado
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
- Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
| | - Víctor Montalvo
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
| | - Judit García-González
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
| | | | - Laia Capilla
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
| | - Aurora Ruiz-Herrera
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
- Departament de Biologia Celular, Fisiologia i Immunologia. Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
| | - Xavier Estivill
- Centre for Genomic Regulation (CRG), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Marta Puig
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
| | - Mario Cáceres
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
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10
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Martínez-Fundichely A, Casillas S, Egea R, Ràmia M, Barbadilla A, Pantano L, Puig M, Cáceres M. InvFEST, a database integrating information of polymorphic inversions in the human genome. Nucleic Acids Res 2014; 42:D1027-32. [PMID: 24253300 PMCID: PMC3965118 DOI: 10.1093/nar/gkt1122] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 10/18/2013] [Accepted: 10/24/2013] [Indexed: 12/27/2022] Open
Abstract
The newest genomic advances have uncovered an unprecedented degree of structural variation throughout genomes, with great amounts of data accumulating rapidly. Here we introduce InvFEST (http://invfestdb.uab.cat), a database combining multiple sources of information to generate a complete catalogue of non-redundant human polymorphic inversions. Due to the complexity of this type of changes and the underlying high false-positive discovery rate, it is necessary to integrate all the available data to get a reliable estimate of the real number of inversions. InvFEST automatically merges predictions into different inversions, refines the breakpoint locations, and finds associations with genes and segmental duplications. In addition, it includes data on experimental validation, population frequency, functional effects and evolutionary history. All this information is readily accessible through a complete and user-friendly web report for each inversion. In its current version, InvFEST combines information from 34 different studies and contains 1092 candidate inversions, which are categorized based on internal scores and manual curation. Therefore, InvFEST aims to represent the most reliable set of human inversions and become a central repository to share information, guide future studies and contribute to the analysis of the functional and evolutionary impact of inversions on the human genome.
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Affiliation(s)
- Alexander Martínez-Fundichely
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain and Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Sònia Casillas
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain and Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Raquel Egea
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain and Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Miquel Ràmia
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain and Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Antonio Barbadilla
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain and Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Lorena Pantano
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain and Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Marta Puig
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain and Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Mario Cáceres
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain and Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
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11
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Cáceres A, Sindi SS, Raphael BJ, Cáceres M, González JR. Identification of polymorphic inversions from genotypes. BMC Bioinformatics 2012; 13:28. [PMID: 22321652 PMCID: PMC3296650 DOI: 10.1186/1471-2105-13-28] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Accepted: 02/09/2012] [Indexed: 01/19/2023] Open
Abstract
Background Polymorphic inversions are a source of genetic variability with a direct impact on recombination frequencies. Given the difficulty of their experimental study, computational methods have been developed to infer their existence in a large number of individuals using genome-wide data of nucleotide variation. Methods based on haplotype tagging of known inversions attempt to classify individuals as having a normal or inverted allele. Other methods that measure differences between linkage disequilibrium attempt to identify regions with inversions but unable to classify subjects accurately, an essential requirement for association studies. Results We present a novel method to both identify polymorphic inversions from genome-wide genotype data and classify individuals as containing a normal or inverted allele. Our method, a generalization of a published method for haplotype data [1], utilizes linkage between groups of SNPs to partition a set of individuals into normal and inverted subpopulations. We employ a sliding window scan to identify regions likely to have an inversion, and accumulation of evidence from neighboring SNPs is used to accurately determine the inversion status of each subject. Further, our approach detects inversions directly from genotype data, thus increasing its usability to current genome-wide association studies (GWAS). Conclusions We demonstrate the accuracy of our method to detect inversions and classify individuals on principled-simulated genotypes, produced by the evolution of an inversion event within a coalescent model [2]. We applied our method to real genotype data from HapMap Phase III to characterize the inversion status of two known inversions within the regions 17q21 and 8p23 across 1184 individuals. Finally, we scan the full genomes of the European Origin (CEU) and Yoruba (YRI) HapMap samples. We find population-based evidence for 9 out of 15 well-established autosomic inversions, and for 52 regions previously predicted by independent experimental methods in ten (9+1) individuals [3,4]. We provide efficient implementations of both genotype and haplotype methods as a unified R package inveRsion.
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Affiliation(s)
- Alejandro Cáceres
- Center for Research in Environmental Epidemiology, and Institut Municipal d'Investigació Mèdica, Barcelona 08003, Spain.
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12
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Biparental inheritance of chromosomal abnormalities in male twins with non-syndromic mental retardation. Eur J Med Genet 2011; 54:e383-8. [PMID: 21426945 DOI: 10.1016/j.ejmg.2011.03.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2010] [Accepted: 03/14/2011] [Indexed: 01/22/2023]
Abstract
In a monozygotic twin couple with mental retardation (MR), we identified a maternally inherited inversion and a paternally inherited translocation: 46,XY,inv(10)(p11.2q21.2)mat,t(9;18)(p22;q21.1)pat. The maternally inherited inv(10) was a benign variant without any apparent phenotypical implications. The translocation breakpoint at 9p was within a cluster of interferon α genes and the 18q21 breakpoint truncated ZBTB7C (zinc finger and BTB containing 7C gene). In addition, analyses with array-CGH revealed a 931 kb maternally inherited deletion on chromosome 8q22 as well as an 875 kb maternally inherited duplication on 5p14. The deletion encompasses the RIM2 (Rab3A-interacting molecule 2), FZD6 (Frizzled homolog 6) and BAALC (Brain and Acute Leukemia Gene, Cytoplasmic) genes and the duplication includes the 5' end of the CDH9 (cadherin 9) gene. Exome sequencing did not reveal any additional mutations that could explain the MR phenotype. The protein products of the above mentioned genes are involved in different aspects of brain development and/or maintenance of the neurons which suggest that accumulation of genetic defects segregating from both parents might be the basis of MR in the twins. This hypothesis was further supported by protein interaction analysis.
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Entesarian M, Carlsson B, Mansouri MR, Stattin EL, Holmberg E, Golovleva I, Stefansson H, Klar J, Dahl N. A chromosome 10 variant with a 12 Mb inversion [inv(10)(q11.22q21.1)] identical by descent and frequent in the Swedish population. Am J Med Genet A 2009; 149A:380-6. [PMID: 19213037 DOI: 10.1002/ajmg.a.32663] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We identified a paracentric inversion of chromosome 10 [inv(10)(q11.22q21.1)] in 0.20% of Swedish individuals (15/7,439) referred for cytogenetic analysis. A retrospective analysis of 8,896 karyotypes from amniocenteses in Sweden revealed a carrier frequency of 0.079% (7/8,896) for the inversion. Cloning and detailed analysis of the inversion breakpoint regions show enrichment for interspersed repeat elements and AT-stretches. The centromeric breakpoint coincides with that of a predicted inversion from HapMap data, which suggests that this region is involved in several chromosome 10 variants. No known gene or predicted transcript are disrupted by the inversion which spans approximately 12 Mb. Carriers from four non-related Swedish families have identical inversion breakpoints and haplotype analysis confirmed that the rearrangement is identical by descent. Diagnosis was retrieved in 6 out of the 15 carriers referred for cytogenetic analysis. No consistent phenotype was found to be associated with the inversion. Our study demonstrates that the inv(10)(q11.22q21.1) is a rare and inherited chromosome variant with a broad geographical distribution in Sweden.
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Affiliation(s)
- Miriam Entesarian
- Department of Genetics and Pathology, Uppsala University, Uppsala, Sweden
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14
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Ionita-Laza I, Laird NM, Raby BA, Weiss ST, Lange C. On the frequency of copy number variants. ACTA ACUST UNITED AC 2008; 24:2350-5. [PMID: 18689430 DOI: 10.1093/bioinformatics/btn421] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
MOTIVATION Estimating the frequency distribution of copy number variants (CNVs) is an important aspect of the effort to characterize this new type of genetic variation. Currently, most studies report a strong skew toward low-frequency CNVs. In this article, our goal is to investigate the frequencies of CNVs. We employ a two-step procedure for the CNV frequency estimation process. We use family information a posteriori to select only the most reliable CNV regions, i.e. those showing high rates of Mendelian transmission. RESULTS Our results suggest that the current skew toward low-frequency CNVs may not be representative of the true frequency distribution, but may be due, among other reasons, to the non-negligible false negative rates that characterize CNV detection methods. Moreover, false positives are also likely, as low-frequency CNVs are hard to detect with small sample sizes and technologies that are not ideally suited for their detection. Without appropriate validation methods, such as incorporation of biologically relevant information (for example, in our case, the transmission of heritable CNVs from parents to offspring), it is difficult to assess the validity of specific CNVs, and even harder to obtain reliable frequency estimates.
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Affiliation(s)
- Iuliana Ionita-Laza
- Department of Biostatistics, Harvard School of Public Health, Boston, MA, USA.
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15
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Thomas NS, Bryant V, Maloney V, Cockwell AE, Jacobs PA. Investigation of the origins of human autosomal inversions. Hum Genet 2008; 123:607-16. [PMID: 18470537 DOI: 10.1007/s00439-008-0510-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2008] [Accepted: 05/01/2008] [Indexed: 11/26/2022]
Abstract
A significant proportion of both pericentric and paracentric inversions have recurrent breakpoints and so could either have arisen through multiple independent events or be identical by descent (IBD) with a single common ancestor. Of two common variant inversions previously studied, the inv(2)(p11q13) was genuinely recurrent while the inv(10)(p11.2q21.2) was IBD in all cases tested. Excluding these two variants we have ascertained 257 autosomal inversion probands at the Wessex Regional Genetics Laboratory. There were 104 apparently recurrent inversions, representing 35 different breakpoint combinations and we speculated that at least some of these had arisen on more than one occasion. However, haplotype analysis identified no recurrent cases among eight inversions tested, including the variant inv(5)(p13q13). The cases not IBD were shown to have different breakpoints at the molecular cytogenetic level. No crossing over was detected within any of the inversions and the founder haplotypes extended for variable distances beyond the inversion breakpoints. Defining breakpoint intervals by FISH mapping identified no obvious predisposing elements in the DNA sequence. In summary the vast majority of human inversions arise as unique events. Even apparently recurrent inversions, with the exception of the inv(2)(p12q13), are likely to be either derived from a common ancestor or to have subtly different breakpoints. Presumably the lack of selection against most inversions allows them to accumulate and disperse amongst different populations over time.
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Affiliation(s)
- N Simon Thomas
- Wessex Regional Genetics Laboratory, Salisbury NHS Foundation Trust, Salisbury District Hospital, Salisbury SP2 8BJ, UK.
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Fickelscher I, Liehr T, Watts K, Bryant V, Barber JCK, Heidemann S, Siebert R, Hertz JM, Tumer Z, Simon Thomas N. The variant inv(2)(p11.2q13) is a genuinely recurrent rearrangement but displays some breakpoint heterogeneity. Am J Hum Genet 2007; 81:847-56. [PMID: 17847011 PMCID: PMC2227935 DOI: 10.1086/521226] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Accepted: 06/28/2007] [Indexed: 02/04/2023] Open
Abstract
Human chromosome 2 contains large blocks of segmental duplications (SDs), both within and between proximal 2p and proximal 2q, and these may contribute to the frequency of the common variant inversion inv(2)(p11.2q13). Despite their being cytogenetically homogeneous, we have identified four different breakpoint combinations by fluorescence in situ hybridization mapping of 40 cases of inv(2)(p11.2q13) of European origin. For the vast majority of inversions (35/40), the breakpoints fell within the same spanning BACs, which hybridized to both 2p11.2 and 2q13 on the normal and inverted homologues. Sequence analysis revealed that these BACs contain a significant proportion of intrachromosomal SDs with sequence homology to the reciprocal breakpoint region. In contrast, BACs spanning the rare breakpoint combinations contain fewer SDs and with sequence homology only to the same chromosome arm. Using haplotype analysis, we identified a number of related family subgroups with identical or very closely related haplotypes. However, the majority of cases were not related, demonstrating for the first time that the inv(2)(p11.2q13) is a truly recurrent rearrangement. Therefore, there are three explanations to account for the frequent observation of the inv(2)(p11.2q13): the majority have arisen independently in different ancestors, while a minority either have been transmitted from a common founder or have different breakpoints at the molecular cytogenetic level.
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Affiliation(s)
- Ina Fickelscher
- Institut fur Humangenetik und Anthropologie, Friedrich-Schiller University, Jena, Germany
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