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Joyce CM, Maher GJ, Dineen S, Suraweera N, McCarthy TV, Coulter J, O'Donoghue K, Seckl MJ, Fitzgerald B. Morphology combined with HER2 D-DISH ploidy analysis to diagnose partial hydatidiform mole: an evaluation audit using molecular genotyping. J Clin Pathol 2024:jcp-2023-209269. [PMID: 38555105 DOI: 10.1136/jcp-2023-209269] [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: 11/04/2023] [Accepted: 01/17/2024] [Indexed: 04/02/2024]
Abstract
AIMS A hydatidiform mole (HM) is classified as complete (CHM) or partial (PHM) based on its morphology and genomic composition. Ancillary techniques are often required to confirm a morphologically suspected PHM diagnosis. This study sought to evaluate the clinical accuracy of PHM diagnosis using morphological assessment supported by HER2 dual-colour dual-hapten in situ hybridisation (D-DISH) ploidy determination. METHODS Over a 2-year period, our unit examined 1265 products of conception (POCs) from which 103 atypical POCs were diagnosed as PHM or non-molar conceptuses with the assistance of HER2 D-DISH ploidy analysis. We retrospectively audited a sample of 40 of these atypical POCs using short tandem repeat genotyping. DNA extracted from formalin-fixed paraffin-embedded tissue was genotyped using 24 polymorphic loci. Parental alleles in placental villi were identified by comparison to those in maternal decidua. To identify triploid PHM cases, we sought three alleles of equal peak height or two alleles with one allele peak twice the height of the other at each locus. RESULTS Thirty-six of the 40 cases (19 PHM and 17 non-molar) were successfully genotyped and demonstrated complete concordance with the original diagnosis. All PHMs were diandric triploid of dispermic origin. In two non-molar diploid cases, we identified suspected trisomies (13 and 18), which potentially explains the pregnancy loss in these cases. CONCLUSIONS This study validates the use of HER2 D-DISH ploidy analysis to support the diagnosis of a morphologically suspected PHM in our practice.
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Affiliation(s)
- Caroline M Joyce
- Pregnancy Loss Research Group, Department of Obstetrics & Gynaecology, University College Cork, Cork, Ireland
- Department of Biochemistry & Cell Biology, University College Cork, Cork, Ireland
- INFANT Research Centre, University College Cork, Cork, Ireland
| | - Geoffrey J Maher
- Trophoblastic Tumour Screening & Treatment Centre, Imperial College NHS Trust, Charing Cross Hospital, London, UK
| | - Susan Dineen
- Pregnancy Loss Research Group, Department of Obstetrics & Gynaecology, University College Cork, Cork, Ireland
- Department of Pathology, Cork University Hospital, Cork, Ireland
| | - Nirosha Suraweera
- Trophoblastic Tumour Screening & Treatment Centre, Imperial College NHS Trust, Charing Cross Hospital, London, UK
| | - Tommie V McCarthy
- Department of Biochemistry & Cell Biology, University College Cork, Cork, Ireland
| | - John Coulter
- Department of Obstetrics & Gynaecology, Cork University Maternity Hospital, Cork, Ireland
| | - Keelin O'Donoghue
- Pregnancy Loss Research Group, Department of Obstetrics & Gynaecology, University College Cork, Cork, Ireland
- INFANT Research Centre, University College Cork, Cork, Ireland
| | - Michael J Seckl
- Trophoblastic Tumour Screening & Treatment Centre, Imperial College NHS Trust, Charing Cross Hospital, London, UK
| | - Brendan Fitzgerald
- Pregnancy Loss Research Group, Department of Obstetrics & Gynaecology, University College Cork, Cork, Ireland
- Department of Pathology, Cork University Hospital, Cork, Ireland
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2
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Massalska D, Bijok J, Kucińska-Chahwan A, Zimowski JG, Ozdarska K, Panek G, Roszkowski T. Triploid pregnancy-Clinical implications. Clin Genet 2021; 100:368-375. [PMID: 34031868 DOI: 10.1111/cge.14003] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 05/17/2021] [Accepted: 05/19/2021] [Indexed: 11/28/2022]
Abstract
Triploidy is a life-limiting genetic aberration resulting from an extra haploid set of chromosomes of paternal (diandric triploidy) or maternal origin (digynic triploidy). Triploidy affects around 1%-2% of all conceptions. The majority of cases is miscarried at early developmental stages. In consequence of genomic imprinting, parental origin affects the phenotype of triploid pregnancies as well as the prevalence and spectrum of related maternal complications. Distinctive ultrasound features of both triploid phenotypes as well as characteristic patterns of biochemical markers may be useful in diagnosis. Molecular confirmation of the parental origin allows to predict the risk of complications, such as gestational trophoblastic neoplasia, hyperthyroidism, hypertension, or preeclampsia associated with the paternal origin of triploidy. Diagnosis of partial hydatidiform mole associated with diandric triploidy is challenging especially in the first trimester pregnancy loss due to the limitations of both histopathology and ultrasound. We present important clinical aspects of triploid pregnancies and indicate unresolved issues demanding further studies.
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Affiliation(s)
- Diana Massalska
- Department of Gynecologic Oncology and Obstetrics, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - Julia Bijok
- Department of Gynecologic Oncology and Obstetrics, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - Anna Kucińska-Chahwan
- Department of Gynecologic Oncology and Obstetrics, Centre of Postgraduate Medical Education, Warsaw, Poland
| | | | - Katarzyna Ozdarska
- Department of Genetics, Institute of Psychiatry and Neurology, Warsaw, Poland
| | - Grzegorz Panek
- Department of Gynecologic Oncology and Obstetrics, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - Tomasz Roszkowski
- Department of Gynecologic Oncology and Obstetrics, Centre of Postgraduate Medical Education, Warsaw, Poland
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3
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Massalska D, Ozdarska K, Roszkowski T, Bijok J, Kucińska-Chahwan A, Panek GM, Zimowski JG. Distribution of diandric and digynic triploidy depending on gestational age. J Assist Reprod Genet 2021; 38:2391-2395. [PMID: 33982170 PMCID: PMC8490569 DOI: 10.1007/s10815-021-02202-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 04/19/2021] [Indexed: 11/18/2022] Open
Abstract
Purpose To establish the distribution of diandric and digynic triploidy depending on gestational age. Methods 107 triploid samples tested prospectively in a single genetic department during a four-year period were analyzed for parental origin of triploidy by Quantitative Fluorescent Polymerase Chain Reaction (QF-PCR) (n=95) with the use of matching parental samples or by MS-MLPA (n=12), when parental samples were unavailable. Tested pregnancies were divided into three subgroups with regard to the gestational age at spontaneous pregnancy loss: <11 gestational weeks, 11–14 gestational weeks, and >14 gestational weeks. Results Diandric triploidy constituted overall 44.9% (46.5% in samples miscarried <11 gestational weeks, 64.3% in samples miscarried between 11 and 14 gestational weeks, and 27.8% in pregnancies which survived >14 gestational weeks). Conclusions The distribution of diandric and digynic triploidy depends on gestational age. The majority of diandric triploid pregnancies is lost in the first trimester of pregnancy. In the second trimester, diandric cases are at least twice less frequent than digynic ones.
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Affiliation(s)
- Diana Massalska
- Department of Gynecologic Oncology and Obstetrics, Centre of Postgraduate Medical Education, Czerniakowska 231, 00-416, Warsaw, Poland.
| | - Katarzyna Ozdarska
- Department of Genetics, Institute of Psychiatry and Neurology, Sobieskiego 9, 02-957, Warsaw, Poland
| | - Tomasz Roszkowski
- Department of Gynecologic Oncology and Obstetrics, Centre of Postgraduate Medical Education, Czerniakowska 231, 00-416, Warsaw, Poland
| | - Julia Bijok
- Department of Gynecologic Oncology and Obstetrics, Centre of Postgraduate Medical Education, Czerniakowska 231, 00-416, Warsaw, Poland
| | - Anna Kucińska-Chahwan
- Department of Gynecologic Oncology and Obstetrics, Centre of Postgraduate Medical Education, Czerniakowska 231, 00-416, Warsaw, Poland
| | - Grzegorz Mieczysław Panek
- Department of Gynecologic Oncology and Obstetrics, Centre of Postgraduate Medical Education, Czerniakowska 231, 00-416, Warsaw, Poland
| | - Janusz Grzegorz Zimowski
- Department of Genetics, Institute of Psychiatry and Neurology, Sobieskiego 9, 02-957, Warsaw, Poland
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4
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Huang TC, Chang KC, Chang JY, Tsai YS, Yang YJ, Chang WC, Mo CF, Yu PH, Chiang CT, Lin SP, Kuo PL. Variants in Maternal Effect Genes and Relaxed Imprinting Control in a Special Placental Mesenchymal Dysplasia Case with Mild Trophoblast Hyperplasia. Biomedicines 2021; 9:biomedicines9050544. [PMID: 34068021 PMCID: PMC8152467 DOI: 10.3390/biomedicines9050544] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/30/2021] [Accepted: 05/10/2021] [Indexed: 11/16/2022] Open
Abstract
Placental mesenchymal dysplasia (PMD) and partial hydatidiform mole (PHM) placentas share similar characteristics, such as placental overgrowth and grape-like placental tissues. Distinguishing PMD from PHM is critical because the former can result in normal birth, while the latter diagnosis will lead to artificial abortion. Aneuploidy and altered dosage of imprinted gene expression are implicated in the pathogenesis of PHM and also some of the PMD cases. Diandric triploidy is the main cause of PHM, whereas mosaic diploid androgenetic cells in the placental tissue have been associated with the formation of PMD. Here, we report a very special PMD case also presenting with trophoblast hyperplasia phenotype, which is a hallmark of PHM. This PMD placenta has a normal biparental diploid karyotype and is functionally sufficient to support normal fetal growth. We took advantage of this unique case to further dissected the potential common etiology between these two diseases. We show that the differentially methylated region (DMR) at NESP55, a secondary DMR residing in the GNAS locus, is significantly hypermethylated in the PMD placenta. Furthermore, we found heterozygous mutations in NLRP2 and homozygous variants in NLRP7 in the mother’s genome. NLRP2 and NLRP7 are known maternal effect genes, and their mutation in pregnant females affects fetal development. The variants/mutations in both genes have been associated with imprinting defects in mole formation and potentially contributed to the mild abnormal imprinting observed in this case. Finally, we identified heterozygous mutations in the X-linked ATRX gene, a known maternal–zygotic imprinting regulator in the patient. Overall, our study demonstrates that PMD and PHM may share overlapping etiologies with the defective/relaxed dosage control of imprinted genes, representing two extreme ends of a spectrum.
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Affiliation(s)
- Tien-Chi Huang
- Institute of Biotechnology, National Taiwan University, Taipei 106, Taiwan; (T.-C.H.); (J.-Y.C.); (W.-C.C.); (C.-F.M.)
| | - Kung-Chao Chang
- Department of Pathology, National Cheng Kung University Hospital, Tainan 704, Taiwan;
| | - Jen-Yun Chang
- Institute of Biotechnology, National Taiwan University, Taipei 106, Taiwan; (T.-C.H.); (J.-Y.C.); (W.-C.C.); (C.-F.M.)
| | - Yi-Shan Tsai
- Department of Radiology, National Cheng Kung University Hospital, Tainan 704, Taiwan;
| | - Yao-Jong Yang
- Department of Pediatrics, National Cheng Kung University Hospital, Tainan 704, Taiwan;
| | - Wei-Chun Chang
- Institute of Biotechnology, National Taiwan University, Taipei 106, Taiwan; (T.-C.H.); (J.-Y.C.); (W.-C.C.); (C.-F.M.)
| | - Chu-Fan Mo
- Institute of Biotechnology, National Taiwan University, Taipei 106, Taiwan; (T.-C.H.); (J.-Y.C.); (W.-C.C.); (C.-F.M.)
| | - Pei-Hsiu Yu
- Department of Obstetrics and Gynecology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan;
- Department of Obstetrics and Gynecology, Kuo General Hospital, Tainan 700, Taiwan
| | - Chun-Ting Chiang
- Department and Graduated Institute of Forensic Medicine, College of Medicine, National Taiwan University, Taipei 106, Taiwan;
| | - Shau-Ping Lin
- Institute of Biotechnology, National Taiwan University, Taipei 106, Taiwan; (T.-C.H.); (J.-Y.C.); (W.-C.C.); (C.-F.M.)
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 115, Taiwan
- Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei 106, Taiwan
- Center for Systems Biology, National Taiwan University, Taipei 106, Taiwan
- Correspondence: (S.-P.L.); (P.-L.K.)
| | - Pao-Lin Kuo
- Department of Obstetrics and Gynecology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan;
- Correspondence: (S.-P.L.); (P.-L.K.)
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5
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Fontoura Oliveira A, Torrão MM, Nogueira R, Ferreira M. Recurrent fetal triploidy: is there a genetic cause? BMJ Case Rep 2021; 14:14/3/e239843. [PMID: 33653854 PMCID: PMC7929808 DOI: 10.1136/bcr-2020-239843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Triploidy is currently understood as a sporadic genetic disorder, with no recognisable risk of recurrence nor identifiable risk factors. In cases of triploidy, chances of thriving through the second trimester of fetal development are very slim, with most of these pregnancies ending as early miscarriage. We report a case of repeated triploid pregnancies in the same woman, from different fathers, achieving the second trimester of pregnancy; elective termination was decided in both cases, after an amniocentesis revealing a triploid karyotype. Both triploid pregnancies are described and compared; prenatal laboratorial markers, sonographic features, clinical course and pathological findings are analysed and matched with fetal autopsy and placental pathological study. Reported findings strongly point to recurrent triploidy of maternal origin, and so the possibility of a genetic predisposition should be considered. Investigation is required to assess the presence of an underlying genetic mechanism in this setting, thus enabling a better genetic/obstetric counselling.
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Affiliation(s)
| | - Maria Manuel Torrão
- Department of Gynecology and Obstetrics, Centro Hospitalar do Médio Ave EPE, Santo Tirso, Portugal
| | - Rosete Nogueira
- Surgical Sciences Research Domain, Life and Health Sciences Research Domain (ICVS), Braga, Portugal,Laboratory of Pathology, CGC Genetics Centro de Genetica Clinica, Porto, Portugal
| | - Manuela Ferreira
- Department of Gynecology and Obstetrics, Centro Hospitalar do Médio Ave EPE, Santo Tirso, Portugal
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6
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Cimadomo D, Capalbo A, Scarica C, Sosa Fernandez L, Rienzi L, Ciriminna R, Minasi MG, Novelli A, De Santis L, Zuccarello D. When embryology meets genetics: the definition of developmentally incompetent preimplantation embryos (DIPE)-the consensus of two Italian scientific societies. J Assist Reprod Genet 2021; 38:319-331. [PMID: 33236289 PMCID: PMC7884494 DOI: 10.1007/s10815-020-02015-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 11/12/2020] [Indexed: 02/06/2023] Open
Abstract
A clear definition of developmentally incompetent preimplantation embryo (DIPE) in literature is still missing, while several scientific societies are discussing this challenging topic. From both a clinical and scientific perspective, the identification of embryos unfit for reproductive purpose is crucial. This aim should be pursued in light of all diagnostic technologies for embryo evaluation, encompassing also genetic analyses, of recent implementation in IVF. The Italian context is characterized by an unusual scenario: embryos can be discarded only if not viable and cannot be used for research purposes either. Therefore, thousands of embryos, diagnosed as affected and/or aneuploid as resulting from preimplantation genetic testing (PGT) and clinically not utilizable, are cryopreserved and stored indefinitely, with important psychological, legal, and financial implications. With the aim of updating the definition of DIPE, also on the basis of the embryo genetic status, the Italian Society of Embryology, Reproduction and Research (SIERR) and the Italian Society of Human Genetic (SIGU) reviewed the literature on this topic, found a consensus, and produced a list of relevant criteria.
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Affiliation(s)
- Danilo Cimadomo
- GeneraLife IVF centers, Clinica Valle Giulia, via G. de Notaris 2b, 00197, Rome, Italy.
| | | | - Catello Scarica
- Center for Reproductive Medicine, Casa di Cura Villa Salaria in Partnership with Institut Marques, Rome, Italy
| | | | - Laura Rienzi
- GeneraLife IVF centers, Clinica Valle Giulia, via G. de Notaris 2b, 00197, Rome, Italy
| | | | | | - Antonio Novelli
- Laboratory of Medical Genetics, IRCCS-Bambino Gesù Children's Hospital, Rome, Italy
| | - Lucia De Santis
- Department of Obstetrics & Gynecology, IVF Unit, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
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7
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Fatemi N, Salehi N, Pignata L, Palumbo P, Cubellis MV, Ramazanali F, Ray P, Varkiani M, Reyhani-Sabet F, Biglari A, Sparago A, Acurzio B, Palumbo O, Carella M, Riccio A, Totonchi M. Biallelic variant in cyclin B3 is associated with failure of maternal meiosis II and recurrent digynic triploidy. J Med Genet 2020; 58:783-788. [PMID: 32938693 PMCID: PMC8551973 DOI: 10.1136/jmedgenet-2020-106909] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 07/07/2020] [Accepted: 07/27/2020] [Indexed: 12/20/2022]
Abstract
Background Triploidy is one of the most common chromosome abnormalities affecting human gestation and accounts for an important fraction of first-trimester miscarriages. Triploidy has been demonstrated in a few cases of recurrent pregnancy loss (RPL) but its molecular mechanisms are unknown. This study aims to identify the genetic cause of RPL associated with fetus triploidy. Methods We investigated genomic imprinting, genotyped sequence-tagged site (STS) markers and performed exome sequencing in a family including two sisters with RPL. Moreover, we evaluated oocyte maturation in vivo and in vitro and effect of the candidate protein variant in silico. Results While features of hydatidiform mole were excluded, the presence of triploidy of maternal origin was demonstrated in the fetuses. Oocyte maturation was deficient and all the maternally inherited pericentromeric STS alleles were homozygous in the fetuses. A deleterious missense variant (p.V1251D) of the cyclin B3 gene (CCNB3) affecting a residue conserved in placental mammals and located in a region that can interact with the cyclin-dependent kinase 1 or cyclin-dependent kinase 2 cosegregated in homozygosity with RPL. Conclusion Here, we report a family in which a damaging variant in cyclin B3 is associated with the failure of oocyte meiosis II and recurrent fetus triploidy, implicating a rationale for CCNB3 testing in RPL.
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Affiliation(s)
- Nayeralsadat Fatemi
- Department of Genetics and Molecular Medicine, School of Medicine, Zanjan University of Medical Sciences (ZUMS), Zanjan, Iran.,Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Najmeh Salehi
- Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Laura Pignata
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies (DiSTABiF), Università degli Studi della Campania "Luigi Vanvitelli", Caserta, Italy.,Institute of Genetics and Biophysics (IGB) "Adriano Buzzati-Traverso", Consiglio Nazionale delle Ricerche (CNR), Napoli, Italy
| | - Pietro Palumbo
- IRCCS-Casa Sollievo della Sofferenza, San Giovanni Rotondo (FG), Italy
| | | | - Fariba Ramazanali
- Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Pierre Ray
- Genetic Epigenetic and Therapies of Infertility, Institute for Advanced Biosciences, INSERM 1209, CNRS UMR 5309, Université Grenoble Alpes, Grenoble F38000, France.,Unité Médicale de génétique de l'infertilité et de diagnostic pré-implantatoire (GI-DPI), Centre Hospitalier Universitaire Grenoble Alpes, Grenoble 38000, France
| | - Maryam Varkiani
- Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Fakhreddin Reyhani-Sabet
- Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Alireza Biglari
- Department of Genetics and Molecular Medicine, School of Medicine, Zanjan University of Medical Sciences (ZUMS), Zanjan, Iran
| | - Angela Sparago
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies (DiSTABiF), Università degli Studi della Campania "Luigi Vanvitelli", Caserta, Italy
| | - Basilia Acurzio
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies (DiSTABiF), Università degli Studi della Campania "Luigi Vanvitelli", Caserta, Italy.,Institute of Genetics and Biophysics (IGB) "Adriano Buzzati-Traverso", Consiglio Nazionale delle Ricerche (CNR), Napoli, Italy
| | - Orazio Palumbo
- IRCCS-Casa Sollievo della Sofferenza, San Giovanni Rotondo (FG), Italy
| | - Massimo Carella
- IRCCS-Casa Sollievo della Sofferenza, San Giovanni Rotondo (FG), Italy
| | - Andrea Riccio
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies (DiSTABiF), Università degli Studi della Campania "Luigi Vanvitelli", Caserta, Italy .,Institute of Genetics and Biophysics (IGB) "Adriano Buzzati-Traverso", Consiglio Nazionale delle Ricerche (CNR), Napoli, Italy
| | - Mehdi Totonchi
- Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran .,Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
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8
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Usefulness of methylation-specific multiplex ligation-dependent probe amplification for identification of parental origin of triploidy. J Hum Genet 2020; 65:889-894. [PMID: 32483273 DOI: 10.1038/s10038-020-0784-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 05/07/2020] [Accepted: 05/19/2020] [Indexed: 11/08/2022]
Abstract
Triploidy is a genetic aberration resulting from an extra haploid set of chromosomes of paternal (diandric) or maternal (digynic) origin. Diandric cases, opposite to digynic ones, may lead to gestational trophoblastic neoplasia (GTN) or generate maternal complications, therefore their identification is crucial, but reproducibility of traditionally used histopathological assessment is poor. The aim of the study was to analyse the usefulness of methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) with probes for two differentially methylated regions (DMR) at chromosome 11p.15.5 for identification of the parental origin of triploidy. 84 triploid DNA samples were tested with MS-MLPA: 34 paternal cases (40.5%) and 50 maternal ones (59.5%) according to the reference results of QF-PCR. Methylation ratio (MR) was calculated. Reference values proposed by the MRC-Holland for diploid samples (MR 0.8-1.2) were used. The values outside these ranges were used to diagnose parental origin of triploidy-paternal (MR > 1.2) or maternal (MR < 0.8). The effectiveness of MS-MLPA was 94.0%. The mean MR in paternal triploidy was 1.7 (SD-0.25; n = 34) compared with 0.56 in maternal triploidy (SD-0.12; n = 50). MR values in paternal and maternal triploidy did not overlap. In five samples (6.0%) parental origin of triploidy could not be accurately established by MS-MLPA, probably due to the maternal cell contamination (MCC). MS-MLPA can be used as a convenient method for distinguishing between paternal and maternal triploidy without the necessity for parental samples testing. It enables adequate selection of the paternal triploid cases for follow up in order to exclude post-molar GTN.
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9
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Lugthart MA, Horenblas J, Kleinrouweler EC, Engels M, Knegt AC, Huijsdens K, van Leeuwen E, Pajkrt E. Prenatal sonographic features can accurately determine parental origin in triploid pregnancies. Prenat Diagn 2020; 40:705-714. [PMID: 32039494 PMCID: PMC7317806 DOI: 10.1002/pd.5666] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 02/02/2020] [Accepted: 02/05/2020] [Indexed: 11/12/2022]
Abstract
Objective To describe the prenatal sonographic features and maternal biochemical markers in triploid pregnancies and to assess whether prenatal phenotype can determine genetic origin. Methods We performed a retrospective multicenter cohort study that included all triploid pregnancies diagnosed between 2000 and 2018 in two Fetal Medicine Units in Amsterdam. Fetal growth, presence of structural anomalies, extra‐fetal anomalies, and maternal biochemical markers were retrieved. Asymmetrical intrauterine growth restriction was diagnosed when the head‐to‐abdominal circumference (HC/AC) ratio was >95th centile. Parental origin was analyzed via molecular genotyping in 46 cases (38.3%). Results One hundred and twenty triploid pregnancies were identified, of which 86 cases (71.6%) were detected before 18 weeks of gestation. Triploidy of maternal origin was found in 32 cases (69.6%) and was associated with asymmetrical growth restriction, a thin placenta, and low pregnancy‐associated plasma protein A and free beta‐human chorionic gonadotrophin (β‐hCG) levels. Triploidy of paternal origin was found in 14 cases (30.4%) and was associated with an increased nuchal translucency, placental molar changes, and a high free β‐hCG. Prospective prediction of the parental origin of the triploidy was made in 30 of the 46 cases based on phenotypical ultrasound presentation, and it was correct in all cases. Conclusion Asymmetrical growth restriction with severe HC/AC discrepancy is pathognomonic of maternal triploidy. Placental molar changes indicate a paternal triploidy. Moreover, triploidy can present with an abnormal first trimester combined test, with serum levels on the extreme end. When available results of maternal serum markers can support the diagnosis of parental origin of the triploidy, an accurate assessment of the parental origin based on prenatal sonographic features is possible, making DNA analysis redundant.
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Affiliation(s)
- Malou A Lugthart
- Department of Obstetrics and Gynecology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Judith Horenblas
- Department of Obstetrics and Gynecology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Emily C Kleinrouweler
- Department of Obstetrics and Gynecology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Melanie Engels
- Department of Obstetrics and Gynecology, Amsterdam UMC, VU University, Amsterdam, The Netherlands
| | - Alida C Knegt
- Department of Clinical Genetics and Genome Diagnostics, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Karin Huijsdens
- Department of Genome Diagnostics, UMC Utrecht, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Elisabeth van Leeuwen
- Department of Obstetrics and Gynecology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Eva Pajkrt
- Department of Obstetrics and Gynecology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
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10
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Carson JC, Hoffner L, Conlin L, Parks WT, Fisher RA, Spinner N, Yatsenko SA, Bonadio J, Surti U. Diploid/triploid mixoploidy: A consequence of asymmetric zygotic segregation of parental genomes. Am J Med Genet A 2018; 176:2720-2732. [PMID: 30302900 DOI: 10.1002/ajmg.a.40646] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 08/14/2018] [Accepted: 09/04/2018] [Indexed: 01/16/2023]
Abstract
Triploidy is the presence of an extra haploid set of chromosomes and can exist in complete or mosaic form. The extra haploid set of chromosomes in triploid cells can be of maternal or paternal origin. Diploid/triploid mixoploidy is a unique form of triploid mosaicism that requires the aberrant segregation of entire parental genomes into distinct blastomere lineages (heterogoneic cell division) at the earliest zygotic divisions. Here we report on eight cases of diploid/triploid mixoploidy from our institution and conduct a comprehensive review of the literature. The parental origin of the extra set of chromosomes was determined in two cases; and, based on phenotypic evidence we propose the parental origin in the other cases. One case with complex mixoploidy appears to have a digynic origin in addition to the involvement of two different sperm. Of our eight cases, only one resulted in the birth of a live healthy child. The other pregnancies ended in miscarriage, elective termination of pregnancy, intrauterine fetal demise or neonatal death. A review of the literature and the results of our cases show that a preponderance of recognized cases of diploid/triploid mixoploidy has a digynic origin.
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Affiliation(s)
- Jason C Carson
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Lori Hoffner
- Magee-Womens Research Institute and Foundation, Pittsburgh, Pennsylvania
| | - Laura Conlin
- Department of Pathology, Children's Hospital of Philadelphia, The University of Pennsylvania, Philadelphia, Pennsylvania.,The Perelman School of Medicine, The University of Pennsylvania, Philadelphia, Pennsylvania
| | - W Tony Parks
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Rosemary A Fisher
- Trophoblastic Tumour Screening and Treatment Centre, Imperial College London, Charing Cross Hospital, London, United Kingdom
| | - Nancy Spinner
- Department of Pathology, Children's Hospital of Philadelphia, The University of Pennsylvania, Philadelphia, Pennsylvania.,The Perelman School of Medicine, The University of Pennsylvania, Philadelphia, Pennsylvania
| | - Svetlana A Yatsenko
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania.,Magee-Womens Research Institute and Foundation, Pittsburgh, Pennsylvania.,Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Jeffrey Bonadio
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Urvashi Surti
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania.,Magee-Womens Research Institute and Foundation, Pittsburgh, Pennsylvania.,Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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11
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Kolarski M, Ahmetovic B, Beres M, Topic R, Nikic V, Kavecan I, Sabic S. Genetic Counseling and Prenatal Diagnosis of Triploidy During the Second Trimester of Pregnancy. Med Arch 2018; 71:144-147. [PMID: 28790549 PMCID: PMC5511524 DOI: 10.5455/medarh.2017.71.144-147] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Introduction: Triploidy is a lethal chromosomal numeric abnormality, characterized on extra haploid set of chromosomes. It occurs in 2 to 3% of conceptuses and accounts for approximately 20% of chromosomally abnormal first-trimester miscarriages. As such, triploidy is estimated to occur in 1 of 3,500 pregnancies at 12 weeks’, 1 in 30,000 at 16 weeks’, and 1 in 250,000 at 20 weeks’ gestation. Case report: We present a case of second-trimester triploidy diagnosed prenataly at our center. 28-years-old gravida with a first spontaneous pregnancy had early gestational hypertension. Ultrasound examination in 146/7 weeks’ gestation revealed asymmetric intrauterine growth retardation. We recommended biochemical maternal serum screening during second trimester of pregnancy (AFP, HCG, uE3). Result of biochemical screening was indication for cytogenetic analysis from amniotic fluid cells and we recommended early amniocentesis in 156/7 weeks’ gestation. Result showed abnormal karyotype of the fetus (69,XXX triploidy), and DNA analysis confirmed Type-2 Diginy. Parents decided to terminate this pregnancy, and it was done at 22 weeks’ gestation. Conclusion: We emphasize the importance of non-invasive prenatal exminationes-biochemical serum screening during second trimester of pregnancy, and ultrasound examinations in prenatal screening of syndroma Down and other chromosomal abnormalities.
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Affiliation(s)
- Milenko Kolarski
- Institute for Child and Young Children Health Care of Vojvodina, Novi Sad, Serbia
| | - Begzudin Ahmetovic
- Department of Gynecology and Obstetrics, General Hospital Brcko District, Brcko, Bosnia and Herzegovina
| | - Maja Beres
- Department of Gynecology and Obstetrics, General Hospital Brcko District, Brcko, Bosnia and Herzegovina
| | - Radomir Topic
- Department of Gynecology and Obstetrics, General Hospital Brcko District, Brcko, Bosnia and Herzegovina
| | - Vedran Nikic
- Department of Gynecology and Obstetrics, General Hospital Brcko District, Brcko, Bosnia and Herzegovina
| | - Ivana Kavecan
- Institute for Child and Young Children Health Care of Vojvodina, Novi Sad, Serbia
| | - Semin Sabic
- Department of Gynecology and Obstetrics, General Hospital Brcko District, Brcko, Bosnia and Herzegovina
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12
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Xu J, Niu W, Peng Z, Bao X, Zhang M, Wang L, Du L, Zhang N, Sun Y. Comparative study of single-nucleotide polymorphism array and next generation sequencing based strategies on triploid identification in preimplantation genetic diagnosis and screen. Oncotarget 2018; 7:81839-81848. [PMID: 27833086 PMCID: PMC5348434 DOI: 10.18632/oncotarget.13247] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 10/14/2016] [Indexed: 11/25/2022] Open
Abstract
Triploidy occurred about 2-3% in human pregnancies and contributed to approximately 15% of chromosomally caused human early miscarriage. It is essential for preimplantation genetic diagnosis and screen to distinct triploidy sensitively. Here, we performed comparative investigations between MALBAC-NGS and MDA-SNP array sensitivity on triploidy detection. Self-correction and reference-correction algorism were used to analyze the NGS data. We identified 5 triploid embryos in 1198 embryos of 218 PGD and PGS cycles using MDA-SNP array, the rate of tripoidy was 4.17‰ in PGS and PGD patients. Our results indicated that the MDA-SNP array was sensitive to digyny and diandry triploidy, MALBAC-NGS combined with self and reference genome correction strategies analyze were not sensitive to detect triploidy. Our study demonstrated that triploidy occurred at 4.17‰ in PGD and PGS, MDA-SNP array could successfully identify triploidy in PGD and PGS and genomic DNA. MALBAC-NGS combined with self and reference genome correction strategies were not sensitive to triploidy.
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Affiliation(s)
- Jiawei Xu
- The First Affiliated Hospital of Zhengzhou University, Centre for Reproductive Medicine, Zhengzhou, Henan 450000, China
| | - Wenbin Niu
- The First Affiliated Hospital of Zhengzhou University, Centre for Reproductive Medicine, Zhengzhou, Henan 450000, China
| | - Zhaofeng Peng
- The First Affiliated Hospital of Zhengzhou University, Centre for Reproductive Medicine, Zhengzhou, Henan 450000, China
| | - Xiao Bao
- The First Affiliated Hospital of Zhengzhou University, Centre for Reproductive Medicine, Zhengzhou, Henan 450000, China
| | - Meixiang Zhang
- The First Affiliated Hospital of Zhengzhou University, Centre for Reproductive Medicine, Zhengzhou, Henan 450000, China
| | - Linlin Wang
- The First Affiliated Hospital of Zhengzhou University, Centre for Reproductive Medicine, Zhengzhou, Henan 450000, China
| | - Linqing Du
- The First Affiliated Hospital of Zhengzhou University, Centre for Reproductive Medicine, Zhengzhou, Henan 450000, China
| | - Nan Zhang
- The First Affiliated Hospital of Zhengzhou University, Centre for Reproductive Medicine, Zhengzhou, Henan 450000, China
| | - Yingpu Sun
- The First Affiliated Hospital of Zhengzhou University, Centre for Reproductive Medicine, Zhengzhou, Henan 450000, China
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13
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Massalska D, Bijok J, Ilnicka A, Jakiel G, Roszkowski T. Triploidy - variability of sonographic phenotypes. Prenat Diagn 2017; 37:774-780. [DOI: 10.1002/pd.5080] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 05/23/2017] [Accepted: 05/25/2017] [Indexed: 01/28/2023]
Affiliation(s)
- Diana Massalska
- I Department of Obstetrics and Gynecology; Centre of Postgraduate Medical Education; Warsaw Poland
| | - Julia Bijok
- I Department of Obstetrics and Gynecology; Centre of Postgraduate Medical Education; Warsaw Poland
| | - Alicja Ilnicka
- Department of Genetics; Institute of Psychiatry and Neurology; Warsaw Poland
| | - Grzegorz Jakiel
- I Department of Obstetrics and Gynecology; Centre of Postgraduate Medical Education; Warsaw Poland
| | - Tomasz Roszkowski
- I Department of Obstetrics and Gynecology; Centre of Postgraduate Medical Education; Warsaw Poland
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14
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Knief U, Forstmeier W. Mapping centromeres of microchromosomes in the zebra finch (Taeniopygia guttata) using half-tetrad analysis. Chromosoma 2016; 125:757-68. [PMID: 26667931 PMCID: PMC5023761 DOI: 10.1007/s00412-015-0560-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 11/12/2015] [Accepted: 11/13/2015] [Indexed: 12/24/2022]
Abstract
Centromeres usually consist of hundreds of kilobases of repetitive sequence which renders them difficult to assemble. As a consequence, centromeres are often missing from assembled genomes and their locations on physical chromosome maps have to be inferred from flanking sequences via fluorescence in situ hybridization (FISH). Alternatively, centromere positions can be mapped using linkage analyses in accidentally triploid individuals formed by half-tetrads (resulting from the inheritance of two chromatids from a single meiosis). The current genome assembly of the zebra finch (Taeniopygia guttata) comprises 32 chromosomes, but only for the ten largest chromosomes centromere positions have been mapped using FISH. We here map the positions of most of the remaining centromeres using half-tetrad analyses. For this purpose, we genotyped 37 zebra finches that were triploid or tetraploid due to inheritance errors (and mostly died as embryos) together with their parents at 64 microsatellite markers (at least two per chromosome). Using the information on centromere positions on the ten largest chromosomes, we were able to identify 12 cases of non-disjunction in maternal meiosis I and 10 cases of non-disjunction in maternal meiosis II. These 22 informative cases allowed us to infer centromere positions on additional 19 microchromosomes in reference to the current genome assembly. This knowledge will be valuable for studies of chromosome evolution, meiotic drive and species divergence in the avian lineage.
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Affiliation(s)
- Ulrich Knief
- Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, 82319, Seewiesen, Germany.
| | - Wolfgang Forstmeier
- Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, 82319, Seewiesen, Germany
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15
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Kalatova B, Jesenska R, Hlinka D, Dudas M. Tripolar mitosis in human cells and embryos: occurrence, pathophysiology and medical implications. Acta Histochem 2015; 117:111-25. [PMID: 25554607 DOI: 10.1016/j.acthis.2014.11.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 11/26/2014] [Accepted: 11/27/2014] [Indexed: 01/08/2023]
Abstract
Tripolar mitosis is a specific case of cell division driven by typical molecular mechanisms of mitosis, but resulting in three daughter cells instead of the usual count of two. Other variants of multipolar mitosis show even more mitotic poles and are relatively rare. In nature, this phenomenon was frequently observed or suspected in multiple common cancers, infected cells, the placenta, and in early human embryos with impaired pregnancy-yielding potential. Artificial causes include radiation and various toxins. Here we combine several pieces of the most recent evidence for the existence of different types of multipolar mitosis in preimplantation embryos together with a detailed review of the literature. The related molecular and cellular mechanisms are discussed, including the regulation of centriole duplication, mitotic spindle biology, centromere functions, cell cycle checkpoints, mitotic autocorrection mechanisms, and the related complicating factors in healthy and affected cells, including post-mitotic cell-cell fusion often associated with multipolar cell division. Clinical relevance for oncology and embryo selection in assisted reproduction is also briefly discussed in this context.
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16
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Filges I, Manokhina I, Peñaherrera MS, McFadden DE, Louie K, Nosova E, Friedman JM, Robinson WP. Recurrent triploidy due to a failure to complete maternal meiosis II: whole-exome sequencing reveals candidate variants. Mol Hum Reprod 2014; 21:339-46. [PMID: 25504873 DOI: 10.1093/molehr/gau112] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 12/05/2014] [Indexed: 01/16/2023] Open
Abstract
Triploidy is a relatively common cause of miscarriage; however, recurrent triploidy has rarely been reported. A healthy 34-year-old woman was ascertained because of 18 consecutive miscarriages with triploidy found in all 5 karyotyped losses. Molecular results in a sixth loss were also consistent with triploidy. Genotyping of markers near the centromere on multiple chromosomes suggested that all six triploid conceptuses occurred as a result of failure to complete meiosis II (MII). The proband's mother had also experienced recurrent miscarriage, with a total of 18 miscarriages. Based on the hypothesis that an inherited autosomal-dominant maternal predisposition would explain the phenotype, whole-exome sequencing of the proband and her parents was undertaken to identify potential candidate variants. After filtering for quality and rarity, potentially damaging variants shared between the proband and her mother were identified in 47 genes. Variants in genes coding for proteins implicated in oocyte maturation, oocyte activation or polar body extrusion were then prioritized. Eight of the most promising candidate variants were confirmed by Sanger sequencing. These included a novel change in the PLCD4 gene, and a rare variant in the OSBPL5 gene, which have been implicated in oocyte activation upon fertilization and completion of MII. Several variants in genes coding proteins playing a role in oocyte maturation and early embryonic development were also identified. The genes identified may be candidates for the study in other women experiencing recurrent triploidy or recurrent IVF failure.
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Affiliation(s)
- I Filges
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada V6T 1Z3 Child and Family Research Institute, Vancouver, BC, Canada V5Z 4H4 Medical Genetics, Department of Biomedicine, University Hospital Basel, Basel 4031, Switzerland
| | - I Manokhina
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada V6T 1Z3 Child and Family Research Institute, Vancouver, BC, Canada V5Z 4H4
| | - M S Peñaherrera
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada V6T 1Z3 Child and Family Research Institute, Vancouver, BC, Canada V5Z 4H4
| | - D E McFadden
- Child and Family Research Institute, Vancouver, BC, Canada V5Z 4H4 Department of Pathology, University of British Columbia, Vancouver, BC, Canada V6T 2B5
| | - K Louie
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada V6T 1Z3 Child and Family Research Institute, Vancouver, BC, Canada V5Z 4H4
| | - E Nosova
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, BC, Canada V5Z 4H4 Centre for Applied Neurogenetics, University of British Columbia, Vancouver, BC, Canada V6T 1Z3
| | - J M Friedman
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada V6T 1Z3 Child and Family Research Institute, Vancouver, BC, Canada V5Z 4H4
| | - W P Robinson
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada V6T 1Z3 Child and Family Research Institute, Vancouver, BC, Canada V5Z 4H4
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17
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Joergensen MW, Niemann I, Rasmussen AA, Hindkjaer J, Agerholm I, Bolund L, Sunde L. Triploid pregnancies: genetic and clinical features of 158 cases. Am J Obstet Gynecol 2014; 211:370.e1-19. [PMID: 24657790 DOI: 10.1016/j.ajog.2014.03.039] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 02/10/2014] [Accepted: 03/14/2014] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The purpose of this study was to analyze the correlation between the genetic constitution and the phenotype in triploid pregnancies. STUDY DESIGN One hundred fifty-eight triploid pregnancies were identified in hospitals in Western Denmark from April 1986 to April 2010. Clinical data and karyotypes were collected retrospectively, and archived samples were retrieved. The parental origin of the genome, either double paternal contribution (PPM) or double maternal contribution (MMP) was determined by an analysis of methylation levels at imprinted sites. RESULTS There were significantly more PPM than MMP cases (P < .01). In MMP cases, the possible karyotypes had similar frequencies, whereas, in PPM cases, 43% had the karyotype 69,XXX, 51% had the karyotype 69,XXY, and 6% had the karyotype 69,XYY. Molar phenotype was seen only in PPM cases. However, PPM cases with a nonmolar phenotype were also seen. For both parental genotypes, various fetal phenotypes were seen at autopsy. Levels of human chorionic gonadotropin in maternal serum were low in MMP cases and varying in PPM cases, some being as low as in the MMP cases. CONCLUSION In a triploid pregnancy, suspicion of hydatidiform mole at ultrasound scanning, by macroscopic inspection of the evacuated tissue, at histology, or because of a high human chorionic gonadotropin in maternal serum level each predict the parental type PPM with a very high specificity. In contrast, the sensitivity of these observations was <100%.
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18
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Chen CP, Su YN, Lin MH, Wang TY, Chern SR, Kuo YL, Chen YT, Wang W. Detection of altered methylation status at 11p15.5 and 7q32 in placental mesenchymal dysplasia. Taiwan J Obstet Gynecol 2014; 53:68-73. [DOI: 10.1016/j.tjog.2013.10.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2013] [Indexed: 11/30/2022] Open
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19
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Wick JB, Johnson KJ, O'Brien J, Wick MJ. Second-trimester diagnosis of triploidy: a series of four cases. AJP Rep 2013; 3:37-40. [PMID: 23943708 PMCID: PMC3699153 DOI: 10.1055/s-0032-1331378] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2012] [Accepted: 07/31/2012] [Indexed: 01/22/2023] Open
Abstract
Triploidy occurs in 2 to 3% of conceptuses and accounts for approximately 20% of chromosomally abnormal first-trimester miscarriages. As such, triploidy is estimated to occur in 1 of 3,500 pregnancies at 12 weeks', 1 in 30,000 at 16 weeks', and 1 in 250,000 at 20 weeks' gestation. We present a series of four cases of second-trimester triploidy diagnosed at our center within a 1-year timeframe. This is remarkable, as the delivery volume at our institution is roughly 2,500/y. All patients were at least 19 weeks' gestation, with multiple abnormalities identified on prenatal ultrasound at 18 to 20 weeks' gestation; all fetuses had lethal anomalies, but anomalies were not consistent between cases. All patients elected for induction of labor before 24 weeks' gestational age. Two of the four cases had amniocentesis and chromosome analysis prior to delivery, and two cases had chromosome analysis performed on fetal tissue after delivery. All fetuses were examined following delivery. This case series demonstrates that the diagnosis of triploidy may not be obvious based on ultrasound and physical examination findings and highlights the importance of routine chromosome analysis on all prenatal diagnoses of multiple congenital anomalies prior to consideration of more complex genetic testing.
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Affiliation(s)
- J B Wick
- St. John's University, Collegeville, Minnesota
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20
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Manokhina I, Hanna CW, Stephenson MD, McFadden DE, Robinson WP. Maternal NLRP7 and C6orf221 variants are not a common risk factor for androgenetic moles, triploidy and recurrent miscarriage. Mol Hum Reprod 2013; 19:539-44. [DOI: 10.1093/molehr/gat019] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
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21
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Ludwig K, Pizzi M, Fassan M, Daolio C, Margiotti K, Consoli F, Salmaso R, Rugge M. "Double trouble" or an amplification of the triploidy phenotype? Fetal Pediatr Pathol 2013; 31:60-5. [PMID: 22515548 DOI: 10.3109/15513815.2012.671444] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Triploidy occurs in about 1 to 3% of clinically recognizable pregnancies and is typically associated with growth restriction, craniofacial dysmorphisms and congenital anomalies. We report the case of a female fetus with prenatal diagnosis of complete triploidy, polysplenia, bilateral cleft-palate, horseshoe-kidneys and bilateral club-feet. Whereas bilateral cleft-palate, horseshoe-kidneys and bilateral club feet are known to be part of the triploidy-associated malformation spectrum, polysplenia, which usually occurs as part of the heterotaxia spectrum, has never been associated with triploidy. An amplification of the triploidy phenotype or a "double trouble".
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Affiliation(s)
- Kathrin Ludwig
- Institute of Pathology, Department of Medical Diagnostic Sciences & Special Therapies, Padova, Italy
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22
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Bourque DK, Peñaherrera MS, Yuen RKC, Van Allen MI, McFadden DE, Robinson WP. The utility of quantitative methylation assays at imprinted genes for the diagnosis of fetal and placental disorders. Clin Genet 2011; 79:169-75. [DOI: 10.1111/j.1399-0004.2010.01443.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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23
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Solomon BD, Rosenbaum KN, Meck JM, Muenke M. Holoprosencephaly due to numeric chromosome abnormalities. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2010; 154C:146-8. [PMID: 20104610 DOI: 10.1002/ajmg.c.30232] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Holoprosencephaly (HPE) is the most common malformation of the human forebrain. When a clinician identifies a patient with HPE, a routine chromosome analysis is often the first genetic test sent for laboratory analysis in order to assess for a structural or numerical chromosome anomaly. An abnormality of chromosome number is overall the most frequently identified etiology in a patient with HPE. These abnormalities include trisomy 13, trisomy 18, and triploidy, though several others have been reported. Such chromosome number abnormalities are almost universally fatal early in gestation or in infancy. Clinical features of specific chromosome number abnormalities may be recognized by phenotypic manifestations in addition to the HPE.
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Affiliation(s)
- Benjamin D Solomon
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
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24
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Boklage CE. Traces of embryogenesis are the same in monozygotic and dizygotic twins: not compatible with double ovulation. Hum Reprod 2009; 24:1255-66. [PMID: 19252194 PMCID: PMC2683734 DOI: 10.1093/humrep/dep030] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Revised: 01/16/2009] [Accepted: 01/22/2009] [Indexed: 11/14/2022] Open
Abstract
Common knowledge of over a century has it that monozygotic and dizygotic twinning events occur by unrelated mechanisms: monozygotic twinning 'splits' embryos, producing anomalously re-arranged embryogenic asymmetries; dizygotic twinning begins with independent ovulations yielding undisturbed parallel embryogeneses with no expectation of departures from singleton outcomes. The anomalies statistically associated with twin births are due to the re-arranged embryos of the monozygotics. Common knowledge further requires that dizygotic pairs are dichorionic; monochorionicity is exclusive to monozygotic pairs. These are fundamental certainties in the literature of twin biology. Multiple observations contradict those common knowledge understandings. The double ovulation hypothesis of dizygotic twinning is untenable. Girl-boy twins differ subtly from all other humans of either sex, absolutely not representative of all dizygotics. Embryogenesis of dizygotic twins differs from singleton development at least as much as monozygotic embryogenesis does, and in the same ways, and the differences between singletons and twins of both zygosities represent a coherent system of re-arranged embryogenic asymmetries. Dizygotic twinning and monozygotic twinning have the same list of consequences of anomalous embryogenesis. Those include an unignorable fraction of dizygotic pairs that are in fact monochorionic, plus many more sharing co-twins' cells in tissues other than a common chorion. The idea that monozygotic and dizygotic twinning events arise from the same embryogenic mechanism is the only plausible hypothesis that might explain all of the observations.
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Affiliation(s)
- Charles E Boklage
- Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA.
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25
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Trichlorfon effects on mouse oocytes following in vivo exposure. Mutat Res 2007; 651:125-30. [PMID: 18069051 DOI: 10.1016/j.mrgentox.2007.10.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2007] [Accepted: 10/28/2007] [Indexed: 11/20/2022]
Abstract
Trichlorfon (TCF) is a widely used pesticide, which according to some epidemiological and experimental data, is suspected of being aneugenic in human and mouse cells. In particular, in vitro studies in mouse oocytes showed the induction of aneuploidy and polyploidy at the first meiotic division and of severe morphological alterations of the second meiotic spindle. We have tested the hypothesis that an acute treatment of mice with TCF might similarly affect chromosome segregation in maturing oocytes. Superovulated MF-1 mice were intraperitoneally injected with 400mg/kg TCF or orally administered with 600mg/kg TCF either at the time of or 4h after human chorionic gonadotrophin (HCG) injection. Oocytes were harvested 17h after HCG and metaphase II chromosomes were cytogenetically analyzed. No significant increase of aneuploid or polyploid cells was detected at any treatment condition. A significant (p<0.001) decrease of metaphases showing premature chromatid separation or premature anaphase II in all TCF-treated groups with respect to controls suggested that TCF treatment may have delayed the first meiotic division. To evaluate possible effects of the pesticide upon the second meiotic division, a group of females orally treated with 600mg/kg TCF at resumption of meiosis was mated with untreated males and zygotes were collected for cytogenetic analysis. No evidence of aneuploidy induction was obtained, but the frequency of polyploid zygotes was increased fivefold over the control level (p<0.01). Such polyploid embryos might have arisen from fertilization of oocytes that were either meiotically delayed and still in metaphase I at fertilization or progressed through anaphase II without cytokinesis. These findings show that in vivo studies on aneuploidy induction in oocytes may yield results different from those obtained by in vitro experiments and that both kinds of data may be necessary for risk assessment of environmentally relevant exposures.
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Lampert KP, Lamatsch DK, Fischer P, Epplen JT, Nanda I, Schmid M, Schartl M. Automictic Reproduction in Interspecific Hybrids of Poeciliid Fish. Curr Biol 2007; 17:1948-53. [DOI: 10.1016/j.cub.2007.09.064] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Revised: 09/26/2007] [Accepted: 09/27/2007] [Indexed: 10/22/2022]
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Migeon BR, Pappas K, Stetten G, Trunca C, Jacobs PA. X inactivation in triploidy and trisomy: the search for autosomal transfactors that choose the active X. Eur J Hum Genet 2007; 16:153-62. [PMID: 17971834 DOI: 10.1038/sj.ejhg.5201944] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Only one X chromosome functions in diploid human cells irrespective of the sex of the individual and the number of X chromosomes. Yet, as we show, more than one X is active in the majority of human triploid cells. Therefore, we suggest that (i) the active X is chosen by repression of its XIST locus, (ii) the repressor is encoded by an autosome and is dosage sensitive, and (iii) the extra dose of this key repressor enables the expression of more than one X in triploid cells. Because autosomal trisomies might help locate the putative dosage sensitive trans-acting factor, we looked for two active X chromosomes in such cells. Previously, we reported that females trisomic for 18 different human autosomes had only one active X and a normal inactive X chromosome. Now we report the effect of triplication of the four autosomes not studied previously; data about these rare trisomies - full or partial - were used to identify autosomal regions relevant to the choice of active X. We find that triplication of the entire chromosomes 5 and 11 and parts of chromosomes 1 and 19 is associated with normal patterns of X inactivation, excluding these as candidate regions. However, females with inherited triplications of 1p21.3-q25.3, 1p31 and 19p13.2-q13.33 were not ascertained. Thus, if a single key dose-sensitive gene induces XIST repression, it could reside in one of these locations. Alternatively, more than one dosage-sensitive autosomal locus is required to form the repressor complex.
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Affiliation(s)
- Barbara R Migeon
- The McKusick - Nathans Institute of Genetic Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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Mechanisms giving rise to triploid zygotes during assisted reproduction. Fertil Steril 2007; 90:49-55. [PMID: 17953968 DOI: 10.1016/j.fertnstert.2007.06.031] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2007] [Revised: 06/04/2007] [Accepted: 06/04/2007] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To review information on the origin of triploid zygotes as gathered from assisted reproduction techniques. DESIGN Identification of relevant literature by a MEDLINE search and own experience on the basis of cytogenetic studies of abnormally fertilized oocytes. SETTING None. PATIENT(S) None. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) None. RESULT(S) Penetration of two haploid spermatozoa or of a single diploid spermatozoon into the oocyte causes diandric triploidy. The first case can be discerned by formation of a total of three pronuclei, whereas the second process will remain undetected, because it involves a female and a single but diploid male pronucleus. Digynic triploidy after intracytoplasmic sperm injection is characterized by nonextrusion of the second polar body and formation of three pronuclei. Digyny can also result from the fertilization of diploid giant oocytes. Depending on how maturation of these gametes proceeds, three or only two pronuclei will be observed. Thus, the size of the pronuclear stage must be considered for a successful identification of the abnormality. Endoreduplication within the female pronucleus is not detectable and may represent another, albeit rare, origin of digynic triploidy. CONCLUSION(S) Routine inspection of the number of pronuclei is not an absolutely reliable tool for excluding the development of triploid embryos. Observations during assisted reproduction may yield valuable information on the origin of triploidy.
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Abstract
Fetal wastage has many causes, but genetic factors are by far the most common. The earlier the pregnancy loss occurs, the greater the likelihood of genetic causation. Among first trimester abortions, 50% to 80% show chromosomal abnormalities, usually aneuploidy. This is greater than all other causes combined. Chromosomal numerical abnormalities can be recurrent and sporadic; failure to take this into account is a major pitfall in many reports addressing causation. Moreover, many causes of fetal wastage that are traditionally considered to be "nongenetic" are actually the result of perturbations of gene products-proteins. Among nongenetic causes of first trimester fetal wastage, the best established are thyroid abnormities; antifetal antibodies; and the inherited and acquired thrombophilias. The latter are more established in the second trimester. Uterine anomalies can lead to second trimester losses. Infections seem uncommon, and alloimmune causes are not validated.
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Affiliation(s)
- Joe Leigh Simpson
- Departments of Obstetrics and Gynecology, Baylor College of Medicine, Houston, Texas, USA.
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Robinson WP, Lauzon JL, Innes AM, Lim K, Arsovska S, McFadden DE. Origin and outcome of pregnancies affected by androgenetic/biparental chimerism. Hum Reprod 2006; 22:1114-22. [PMID: 17185351 DOI: 10.1093/humrep/del462] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Androgenetic diploid cells confined to the placenta have recently been reported in several cases of normally developed fetuses in association with placental mesenchymal dysplasia (PMD). METHODS AND RESULTS We investigated two singleton, mildly growth-restricted, female pregnancies ascertained on the basis of PMD. One case had liver hemangiomas and both infants had multiple skin hemangiomas. Post-natal development was normal. Molecular marker analysis confirmed the diagnosis of androgenetic and normal mixed cell populations in the placenta. Both cases derived from a single maternal genome (M1) and two distinct paternal genomes (P1 and P2). In one case, the androgenetic cell population contained both paternal genomes (P1P2), with one shared in common with the biparental (M1P1) population. In the second case, the androgenetic lineage showed complete homozygosity (P2P2) for a paternal genome not common to the biparental cell population. CONCLUSION These new PMD cases help to define the range of possible clinical presentations of androgenetic/biparental mosaicism or chimerism. Placentas with androgenetic/biparental chimeric cell populations may derive from a single tri-pronuclear (3PN) zygote in which one or more parental genomes are not equally apportioned to the daughter cells in the first cell division.
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Affiliation(s)
- Wendy P Robinson
- Department of Medical Genetics, University of British Columbia, British Columbia, Canada.
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Abstract
Human spontaneous chimerism, with one body built from cells of both twins of a dizygotic (DZ) pair, is supposed to be extremely rare, arising from the exchange of blood cells through placental anastomoses. Mosaicism is supposed to be far more common, arising from single zygotes by embryonic mutation. Because typical diagnosis of mosaicism can neither identify nor exclude chimerism, 'mosaicism' may often be chimerism undiscovered. Evidence shows chimerism arises primarily from DZ embryo fusion and is not rare, although it has negligible probability under the hypothesis of independent double ovulation and independent embryogenesis. If, instead, DZ twin embryos begin development as a single cell mass, chimerism is likely. This would be consistent with observations that DZ twins develop as differently from singletons as monozygotic twins do with regard to embryogenic establishment of asymmetries of midline neural-crest-driven structures of brain, face and heart. Chimerism is a significant component of human embryonic development that deserves closer attention as a mechanism of developmental variation. The 'common knowledge' understanding of twinning mechanisms is at best inadequate. The importance of the difference lies in what we can learn from chimerism about human embryogenesis and the cellular origins of structures and functions basic to the business of becoming human.
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Affiliation(s)
- Charles E Boklage
- Laboratory of Behavioral and Developmental Genetics, Department of Pediatrics, 3N72 Brody School of Medicine, East Carolina University, Greenville NC 27834, USA.
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Abstract
The phenotypes of triploid fetuses and placentae are now well established and known to correlate with parental origin of the extra haploid set of chromosomes. In fetuses, it is not clear whether there is a direct parent of origin effect on the fetus itself or if the phenotypes are the result of growth differences influenced by abnormalities in growth and function of the placenta. Examining the phenotype of triploid embryos at an earlier stage in gestation, when the placenta effects may be less pronounced, could help clarify this question. A phenotype characteristic of triploidy in the embryonic period has been described; however, parental origin was not determined in these embryonic cases. In the present study, a population of triploid embryos is assessed to determine if there is a correlation between parental origin and phenotype. Parental origin was determined in 27 first trimester miscarriages. Digyny accounted for 19 cases and diandry for eight cases. Assessment of embryonic phenotype with parental origin showed no correlation between the phenotype of the embryo and parental origin of the extra haploid set. While there may be subtle effects of imprinting on embryonic development, they are not as obvious as they are in the mouse, consistent with the general trend of fewer imprinted genes in human beings compared with the mouse.
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Tham B, Everard J, Tidy J, Drew D, Hancock B. Gestational trophoblastic disease in the Asian population of Northern England and North Wales. BJOG 2003. [DOI: 10.1046/j.1471-0528.2003.01413.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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van de Laar I, Rabelink G, Hochstenbach R, Tuerlings J, Hoogeboom J, Giltay J. Diploid/triploid mosaicism in dysmorphic patients. Clin Genet 2002; 62:376-82. [PMID: 12431252 DOI: 10.1034/j.1399-0004.2002.620504.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Diploid/triploid mosaicism is a dysmorphology syndrome consisting of mental retardation, truncal obesity, body and/or facial asymmetry, growth retardation, hypotonia, a small phallus, malformed low-set ears and micrognathia. In 75% of the cases, the blood karyotype is normal and the diagnosis can only be established after analysis of cultured fibroblasts. This chromosome abnormality may therefore be underdiagnosed. This paper focuses on the identification of mentally retarded and dysmorphic patients with diploid/triploid mosaicism. Detailed clinical description of well-defined patients may help in deciding if a skin biopsy for karyotyping of fibroblasts should be taken. Three new cases are presented, in which DNA marker analysis showed that the extra set of chromosomes in each case was derived from the mother. We present a review of 25 cases described in the literature and we discuss the inclusion of a second polar body into an early diploid embryo as the most likely mechanism.
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Affiliation(s)
- I van de Laar
- Department of Medical Genetics, University Medical Center, Utrecht, the Netherlands
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Robinson WP, McFadden DE, Stephenson MD. The origin of abnormalities in recurrent aneuploidy/polyploidy. Am J Hum Genet 2001; 69:1245-54. [PMID: 11675616 PMCID: PMC1235536 DOI: 10.1086/324468] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2001] [Accepted: 09/20/2001] [Indexed: 11/03/2022] Open
Abstract
Recurrent miscarriage due to sporadic chromosomal abnormalities may simply be a consequence of the dramatic increase of trisomic conceptions with increased maternal age. However, it is also possible that some couples are at increased risk of abnormalities as a result of gonadal mosaicism, factors affecting chromosome structure and segregation, increased sperm aneuploidy in the male partner, or accelerated "aging" of the ovaries. We report cytogenetic and molecular findings from 122 spontaneous abortions (SAs) from 54 couples who were ascertained as having two or more documented aneuploid or polyploid SAs. The distribution of abnormalities in this group was similar to those from 307 SAs that involved chromosome abnormalities and were diagnosed at the same center but did not involve documented recurrent aneuploidy/polyploidy. Although recurrence of the same abnormality was observed in eight families, this number was equal to that expected by chance, indicating that gonadal mosaicism is rarely the explanation for recurrence. The origin of the abnormality was determined in 37 SAs from 23 of the couples in the study. A maternal meiotic origin was involved in 30 trisomies and in 1 triploid SA; 3 additional maternal trisomies were of possible somatic origin. A paternal origin was found in the remaining two trisomies and in one triploid SA. In addition, one double trisomy was the consequence of both a maternal and a paternal meiotic error. These results confirm that the etiology of trisomy is predominantly a result of meiotic errors related to increased maternal age, regardless of whether the couple has experienced one or multiple aneuploid SAs. Furthermore, this is true even when a second SA involves the same abnormality. Nonetheless, these data do not exclude some population variability in risk for aneuploidy.
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Affiliation(s)
- W P Robinson
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
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