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Priya K, Setty M, Babu UV, Pai KSR. Implications of environmental toxicants on ovarian follicles: how it can adversely affect the female fertility? ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:67925-67939. [PMID: 34628616 PMCID: PMC8718383 DOI: 10.1007/s11356-021-16489-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 09/07/2021] [Indexed: 05/06/2023]
Abstract
The pool of primordial follicles formed in the ovaries during early development determines the span and quality of fertility in the reproductive life of a woman. As exposure to occupational and environmental toxicants (ETs) has become inevitable, consequences on female fertility need to be established. This review focuses on the ETs, especially well-studied prototypes of the classes endocrine disrupting chemicals (EDCs), heavy metals, agrochemicals, cigarette smoke, certain chemicals used in plastic, cosmetic and sanitary product industries etc that adversely affect the female fertility. Many in vitro, in vivo and epidemiological studies have indicated that these ETs have the potential to affect folliculogenesis and cause reduced fertility in women. Here, we emphasize on four main conditions: polycystic ovary syndrome, primary ovarian insufficiency, multioocytic follicles and meiotic defects including aneuploidies which can be precipitated by ETs. These are considered main causes for reduced female fertility by directly altering the follicular recruitment, development and oocytic meiosis. Although substantial experimental evidence is drawn with respect to the detrimental effects, it is clear that establishing the role of one ET as a risk factor in a single condition is difficult as multiple conditions have common risk factors. Therefore, it is important to consider this as a matter of public and wildlife health.
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Affiliation(s)
- Keerthi Priya
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Manjunath Setty
- Department of Pharmacognosy, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Uddagiri Venkanna Babu
- Phytochemistry Department, R & D Centre, The Himalaya Drug Company, Makali, Tumkur Road, Bangalore, Karnataka, 562162, India
| | - Karkala Sreedhara Ranganath Pai
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India.
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Szydłowska A, Ladstätter S, Tachibana K. Manipulating Cohesin Levels in Live Mouse Oocytes. Methods Mol Biol 2018; 1818:113-128. [PMID: 29961260 DOI: 10.1007/978-1-4939-8603-3_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The cohesin complex is essential for chromosome segregation in mitosis and meiosis. Cohesin is a tripartite protein complex that holds sister chromatids together from DNA replication until anaphase. In mammals, meiotic DNA replication occurs in oogonia of embryos and chromosome segregation occurs in oocytes of sexually mature females. Sister chromatid cohesion establishment and chromosome segregation are thus separated by months in the mouse and decades in the human. The meiotic cohesin complex that maintains sister chromatid cohesion must therefore hold replicated sisters together for a long time in oocytes. Remarkably, this is achieved by establishing cohesion exclusively in prenatal oocytes. Meiotic cohesion in females is maintained without detectable turnover and cohesin is therefore thought to be a long-lived protein complex. Nevertheless, the lifespan of cohesin molecules is limited as chromosomal cohesin levels decline with maternal age. The age-related loss of cohesin and weakened cohesion correlate with an age-related increase in chromosome missegregation of meiosis I oocytes that results in aneuploid eggs. Therefore, loss of chromosomal cohesin has been proposed to be a leading cause of the maternal age effect. To better understand cohesin deterioration in oocytes, it is crucial to gain insights into mammalian cohesion establishment and maintenance mechanisms by manipulating cohesin in live oocytes.This chapter describes techniques that address the manipulation of meiotic cohesin levels in mouse oocytes. First, we describe how cohesin can be efficiently removed from meiotic chromosomes by injecting mRNA encoding TEV protease in live oocytes expressing cohesin with engineered TEV recognition sites, followed by imaging. Secondly, we describe how cohesin expression can be induced during different stages of oocyte development using genetically modified mouse strains. In particular, we describe how to determine the deletion timing of germline-specific Cre recombinases using β-galactosidase staining of fetal ovaries. Lastly, we provide guidance on how to quantify cohesin levels on metaphase I chromosome spreads.
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Affiliation(s)
- Anna Szydłowska
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter, Vienna, Austria
| | - Sabrina Ladstätter
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter, Vienna, Austria
| | - Kikuë Tachibana
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter, Vienna, Austria.
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Association between telomere length and chromosome 21 nondisjunction in the oocyte. Hum Genet 2015; 134:1263-70. [PMID: 26407969 DOI: 10.1007/s00439-015-1603-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 09/15/2015] [Indexed: 10/23/2022]
Abstract
Chromosome 21 nondisjunction in oocytes is the most common cause of trisomy 21, the primary chromosomal abnormality responsible for Down syndrome (DS). This specific type of error is estimated to account for over 90 % of live births with DS, with maternal age being the best known risk factor for chromosome 21 nondisjunction. The loss of telomere length and the concomitant shortening of chromosomes are considered a biological marker for aging. Thus, we tested the hypothesis that mothers who had a maternal nondisjunction error leading to a live birth with DS (n = 404) have shorter telomeres than mothers with live births without DS (n = 42). In effect, our hypothesis suggests that mothers of children with DS will appear "biologically older" as compared to the mothers of euploid children. We applied a quantitative PCR assay to measure the genome-wide relative telomere length to test this hypothesis. The results of our study support the hypothesis that young mothers of DS babies are "biologically older" than mothers of euploid babies in the same age group and supports telomere length as a biomarker of age and hence risk for chromosome nondisjunction.
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Abstract
Miscarriage is a very common occurrence in humans. This paper sets out to present published data on research that has provided increased understanding of pregnancy failure. Clarification of definitions, exploring the range of failures from preclinical to later pregnancy losses, and the scientific tools employed to find information on the losses have been documented. What is now understood, which tools work best, and the associated limitations are all discussed. Early studies used cytogenetic methods and tissue culture to obtain results. Improvements in laboratory tools such as better tissue culture incubators, inverted microscopes, laminar flow hoods, improvements in culture media, all contributed to obtaining more results for patients. These studies demonstrated the significant contribution of unbalanced chromosomal karyotypes to pregnancy failure. Maternal age as a contributing factor in trisomy was clearly demonstrated. First trimester miscarriage exhibits very high cytogenetic abnormality; in contrast to very low rates in later losses. Combining data across all time periods of pregnancy will affect the significance of chromosomal error in the early pregnancy failures. Cytogenetic methods investigate whole genomes, and are considered to represent the standard against which new methods must be validated. New molecular genetic methods provide the opportunity to examine samples without the necessity of tissue culture. Techniques may be site-specific or whole genome. Fluorescent in situ hybridisation (FISH), comparative genomic hybridisation (CGH), array-based CGH, single nucleotide polymorphism (SNP) detection, quantitative polymerase chain reaction (qPCR), and quantitative fluorescent PCR (QF-PCR), have all been utilised. In comparison studies with classical/conventional cytogenetics, each newer method offers advantages and limitations. At the present time, a combined approach using conventional and molecular methods will elucidate the cause of miscarriage for almost all samples. In a clinical setting this would be optimum.
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Affiliation(s)
- Kathy Hardy
- Cyto Labs Pty Ltd, Bentley, Western Australia
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Fauser BCJM, Devroey P, Diedrich K, Balaban B, Bonduelle M, Delemarre-van de Waal HA, Estella C, Ezcurra D, Geraedts JPM, Howles CM, Lerner-Geva L, Serna J, Wells D. Health outcomes of children born after IVF/ICSI: a review of current expert opinion and literature. Reprod Biomed Online 2013; 28:162-82. [PMID: 24365026 DOI: 10.1016/j.rbmo.2013.10.013] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 10/03/2013] [Accepted: 10/08/2013] [Indexed: 01/28/2023]
Abstract
The Sixth Evian Annual Reproduction (EVAR) Workshop Group Meeting was held to evaluate the impact of IVF/intracytoplasmic sperm injection on the health of assisted-conception children. Epidemiologists, reproductive endocrinologists, embryologists and geneticists presented data from published literature and ongoing research on the incidence of genetic and epigenetic abnormalities and congenital malformations in assisted-conception versus naturally conceived children to reach a consensus on the reasons for potential differences in outcomes between these two groups. IVF-conceived children have lower birthweights and higher peripheral fat, blood pressure and fasting glucose concentrations than controls. Growth, development and cognitive function in assisted-conception children are similar to controls. The absolute risk of imprinting disorders after assisted reproduction is less than 1%. A direct link between assisted reproduction and health-related outcomes in assisted-conception children could not be established. Women undergoing assisted reproduction are often older, increasing the chances of obtaining abnormal gametes that may cause deviations in outcomes between assisted-conception and naturally conceived children. However, after taking into account these factors, it is not clear to what extent poorer outcomes are due to the assisted reproduction procedures themselves. Large-scale, multicentre, prospective epidemiological studies are needed to investigate this further and to confirm long-term health consequences in assisted-conception children. Assisted reproduction treatment is a general term used to describe methods of achieving pregnancy by artificial means and includes IVF and sperm implantation. The effect of assisted reproduction treatment on the health of children born using these artificial methods is not fully understood. In April 2011, fertility research experts met to give presentations based on research in this area and to look carefully at the evidence for the effects of assisted reproduction treatment on children's health. The purpose of this review was to reach an agreement on whether there are differences in the health of assisted-conception children with naturally conceived children. The researchers discovered no increased risk in birth defects in assisted-conception children compared with naturally conceived children. They found that IVF-conceived children have lower birth weights and higher fat under the skin, higher blood pressure and higher fasting glucose concentrations than naturally conceived children; however, growth, development and cognitive function are similar between groups. A very low risk of disorders of genetic control was observed in assisted-conception children. Overall, there did not appear to be a direct link between assisted reproduction treatment and children's health. The researchers concluded that the cause of some differences in the health of children conceived using assisted reproduction treatment may be due to the age of the woman receiving treatment. Large-scale, research studies are needed to study the long-term health of children conceived using assisted reproduction treatment.
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Affiliation(s)
- B C J M Fauser
- Department of Reproductive Medicine and Gynaecology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
| | - P Devroey
- Center for Reproductive Medicine, Vrije Universiteit Brussel, Laarbeeklaan 101, 1090 Brussels, Belgium
| | - K Diedrich
- Department of Obstetrics and Gynecology, University Clinic of Schleswig-Holstein, Campus Luebeck, 23538 Luebeck, Germany
| | - B Balaban
- Assisted Reproduction Unit, American Hospital of Istanbul, Guzelbahce Sokak No 20, Nisantasi, Istanbul 34365, Turkey
| | - M Bonduelle
- Centre for Medical Genetics, Vrije Universiteit Brussel, Laarbeeklaan 101, 1090 Brussels, Belgium
| | | | - C Estella
- Fundación Instituto Valenciano de Infertilidad (FIVI), Valencia University, and Instituto Universitario IVI/INCLIVA, Parc Científic Universitat de València C/Catedrático Agustín Escardino n(o) 9, Edificio 3, 46980 Paterna, Spain; Departamento de Biología Molecular and Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), Universidad Autónoma de Madrid, Madrid, Spain
| | - D Ezcurra
- Global Development and Medical Unit, Merck Serono SA Geneva, Chemin des Mines 9, 1202 Geneva, Switzerland
| | - J P M Geraedts
- Department of Genetics and Cell Biology, Research Institute GROW, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands
| | - C M Howles
- Global Development and Medical Unit, Merck Serono SA Geneva, Chemin des Mines 9, 1202 Geneva, Switzerland
| | - L Lerner-Geva
- Woman and Child Health Research Unit, Gertner Institute for Epidemiology and Health Policy Research, Tel Hashomer 52621, Israel
| | - J Serna
- Instituto Valenciano de Infertilidad (IVI) Zaragoza, C/María Zambrano, 31, 50018 Zaragoza, Spain
| | - D Wells
- University of Oxford, Nuffield Department of Obstetrics and Gynaecology, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
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El-Gilany AH, Yahia S, Shoker M, El-Dahtory F. Cytogenetic and comorbidity profile of Down syndrome in Mansoura University Children's Hospital, Egypt. INDIAN JOURNAL OF HUMAN GENETICS 2012; 17:157-63. [PMID: 22345986 PMCID: PMC3276983 DOI: 10.4103/0971-6866.92092] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND: Down syndrome (DS) is the most common chromosomal disorder. It has three chromosomal patterns. AIM: To determine the cytogenetic and comorbidity profiles of DS in the Genetic Unit of Mansoura University Children's Hospital, Mansoura, Egypt. MATERIALS AND METHODS: A retrospective analysis was performed on the case records of 712 cytogenetically diagnosed cases of DS at the Genetic Unit of Mansoura University Children's Hospital, Egypt, during a 10-year period. RESULTS: About 19% of the cases had one or more cardiac anomalies and about 8% were hypothyroid. Nondisjunction was the most common type of abnormality, followed by translocation and lastly mosaic: 96.1, 3.1, and 0.8%, respectively. Hypothyroidism was significantly more common in translocation and mosaic karyotypes than in the nondisjunction karyotypes. First and second birth orders were significantly higher in the translocation and mosaic groups than in the nondisjunction group. Mothers are significantly older at the index pregnancy in the nondisjunction group than in the other two groups. We compared our findings with those of previous studies. CONCLUSION: Knowing karyotype of DS will help in genetic counseling of the parents. Wide-scale national community-based survey with DS registry could help in estimating the size of the problem.
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Affiliation(s)
- Abdel-Hady El-Gilany
- Department of Public Health, Mansoura University Children's Hospital, Mansoura, Egypt
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Morris CR, Haigh S, Cuthbert G, Crosier M, Harding F, Wolstenholme J. Origin of trisomy: no evidence to support the ovarian mosaicism theory. Prenat Diagn 2012; 32:668-73. [DOI: 10.1002/pd.3885] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Charlotte Rose Morris
- Northern Genetics Service; Institute of Genetic Medicine; Central Parkway Newcastle upon Tyne NE1 3BZ UK
| | - Shaun Haigh
- Northern Genetics Service; Institute of Genetic Medicine; Central Parkway Newcastle upon Tyne NE1 3BZ UK
| | - Gavin Cuthbert
- Northern Genetics Service; Institute of Genetic Medicine; Central Parkway Newcastle upon Tyne NE1 3BZ UK
| | - Moira Crosier
- Human Developmental Biology Resource, Institute of Genetic Medicine; Newcastle University; Central Parkway Newcastle upon Tyne NE1 3BZ UK
| | - Fiona Harding
- Northern Genetics Service; Institute of Genetic Medicine; Central Parkway Newcastle upon Tyne NE1 3BZ UK
| | - John Wolstenholme
- Northern Genetics Service; Institute of Genetic Medicine; Central Parkway Newcastle upon Tyne NE1 3BZ UK
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Zerem A, Vinkler C, Michelson M, Leshinsky-Silver E, Lerman-Sagie T, Lev D. Mosaic marker chromosome 16 resulting in 16q11.2-q12.1 gain in a child with intellectual disability, microcephaly, and cerebellar cortical dysplasia. Am J Med Genet A 2011; 155A:2991-6. [DOI: 10.1002/ajmg.a.34316] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Accepted: 08/20/2011] [Indexed: 11/06/2022]
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Hussin J, Roy-Gagnon MH, Gendron R, Andelfinger G, Awadalla P. Age-dependent recombination rates in human pedigrees. PLoS Genet 2011; 7:e1002251. [PMID: 21912527 PMCID: PMC3164683 DOI: 10.1371/journal.pgen.1002251] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Accepted: 06/22/2011] [Indexed: 01/27/2023] Open
Abstract
In humans, chromosome-number abnormalities have been associated with altered recombination and increased maternal age. Therefore, age-related effects on recombination are of major importance, especially in relation to the mechanisms involved in human trisomies. Here, we examine the relationship between maternal age and recombination rate in humans. We localized crossovers at high resolution by using over 600,000 markers genotyped in a panel of 69 French-Canadian pedigrees, revealing recombination events in 195 maternal meioses. Overall, we observed the general patterns of variation in fine-scale recombination rates previously reported in humans. However, we make the first observation of a significant decrease in recombination rates with advancing maternal age in humans, likely driven by chromosome-specific effects. The effect appears to be localized in the middle section of chromosomal arms and near subtelomeric regions. We postulate that, for some chromosomes, protection against non-disjunction provided by recombination becomes less efficient with advancing maternal age, which can be partly responsible for the higher rates of aneuploidy in older women. We propose a model that reconciles our findings with reported associations between maternal age and recombination in cases of trisomies.
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Affiliation(s)
- Julie Hussin
- Department of Biochemistry, Faculty of Medicine, University of Montreal, Montreal, Canada
- Sainte-Justine Hospital Research Centre, Montreal, Canada
| | - Marie-Hélène Roy-Gagnon
- Sainte-Justine Hospital Research Centre, Montreal, Canada
- Department of Social and Preventive Medicine, Faculty of Medicine, University of Montreal, Montreal, Canada
| | | | - Gregor Andelfinger
- Sainte-Justine Hospital Research Centre, Montreal, Canada
- Department of Pediatrics, Faculty of Medicine, University of Montreal, Montreal, Canada
| | - Philip Awadalla
- Sainte-Justine Hospital Research Centre, Montreal, Canada
- Department of Pediatrics, Faculty of Medicine, University of Montreal, Montreal, Canada
- * E-mail:
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Abstract
PURPOSE OF REVIEW The relationship between increasing maternal age and trisomy has been recognized for over 50 years and is one of the most important etiological factors associated with any human genetic disorder. Specifically, the risk of trisomy in a clinically recognized pregnancy rises from about 2-3% for women in their twenties to an astounding 30% or more for women in their forties. Thus, as women approach the end of their child-bearing years, errors of chromosome segregation represent the most important impediment to a successful pregnancy. RECENT FINDINGS Despite the clinical importance of this relationship, we do not understand how age affects the likelihood of producing a normal egg. Errors that affect chromosome segregation could occur at several stages during the development of the oocyte: in the fetal ovary, either during the mitotic proliferation of oogonia or the early stages of meiosis; in the 'dictyate' oocyte, during the 10-50-year period of meiotic arrest; or during the final stages of oocyte growth and maturation, when meiosis resumes and the meiotic divisions take place. Recent evidence from studies of human oocytes and trisomic conceptions and from studies in model organisms implicates errors at each of these stages. SUMMARY It seems likely that there are multiple causes of human age-related nondisjunction, complicating our efforts to understand - and, ultimately, to provide preventive measures for - errors associated with increasing maternal age.
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Affiliation(s)
- Terry Hassold
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, Washington 99164, USA.
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Garcia-Cruz R, Casanovas A, Brieno-Enriquez M, Robles P, Roig I, Pujol A, Cabero L, Durban M, Garcia Caldes M. Cytogenetic analyses of human oocytes provide new data on non-disjunction mechanisms and the origin of trisomy 16. Hum Reprod 2009; 25:179-91. [DOI: 10.1093/humrep/dep347] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Murthy SK, Malhotra AK, Mani S, Shara MEA, Al-Rowaished EEM, Naveed S, Alkhayat AI, Alali MT. Incidence of Down syndrome in Dubai, UAE. Med Princ Pract 2007; 16:25-8. [PMID: 17159360 DOI: 10.1159/000096136] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2005] [Accepted: 05/14/2006] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE To describe incidence of Down syndrome in Dubai, United Arab Emirates (UAE). SUBJECTS AND METHODS A total of 63,398 newborn babies in Dubai (24,250 UAE nationals and 39,148 non-UAE) during a 5-year period of 1999-2003 were routinely examined by experienced nurses, neonatologists, pediatricians and/or general practitioners for symptoms of Down syndrome. Those suspected with Down syndrome were referred to the cytogenetic laboratory for karyotyping. RESULTS A total of 141 cases were confirmed cytogenetically as Down syndrome. Of these, 139 were trisomy 21 and of the remaining 2, 1 was a translocation and the other a mosaic. Theoverall incidence of Down syndrome in Dubai was 1/449 live births (2.2 per 1,000); 1/319 live births (3.13 per 1,000) among UAE nationals and 1/602 live births (1.66 per 1,000) among non-UAE nationals. The mean maternal age of UAE national mothers was 33.48 +/- 8.08, with 41.66% of the mothers being in the advanced maternal age group (>35 years). The higher incidence of Down syndrome among UAE nationals is comparable to incidences reported for other Arab populations in the Middle Eastern region. Advanced maternal age, with mothers bearing children until their 50s and higher parity, appear to be the major contributing factors for the increased incidence. CONCLUSION The study indicates the need to provide efficient genetic counseling and to introduce an effective antenatal screening program and prenatal diagnostic services to reduce the psychological and genetic burden on the families and community.
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Affiliation(s)
- Sabita K Murthy
- Department of Genetics, Al Wasl Hospital, Department of Health and Medical Services, Dubai, UAE.
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Bianco K, Caughey AB, Shaffer BL, Davis R, Norton ME. History of miscarriage and increased incidence of fetal aneuploidy in subsequent pregnancy. Obstet Gynecol 2006; 107:1098-102. [PMID: 16648416 DOI: 10.1097/01.aog.0000215560.86673.22] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The purpose of this study was to examine the association between history of spontaneous abortion and aneuploidy in a subsequent pregnancy. METHODS This was a retrospective cohort study of women who underwent fetal karyotype analysis with amniocentesis or chorionic villus sampling at a single prenatal diagnosis center. Information on spontaneous abortions, parity, maternal age, ethnicity, type of prenatal diagnosis, and karyotype was assessed. Univariable and multivariable analyses were conducted. RESULTS A total of 46,939 women were included in our analysis. Women with no prior spontaneous abortions had a 1.39% risk for any aneuploidy. In women with one prior spontaneous abortion, this risk increased to 1.67%; for women with 2 previous spontaneous abortions, the risk increased to 1.84%; and for those women who had had 3 or more prior spontaneous abortions, the risk increased further to 2.18% (P < .007). When controlling for maternal age, parity, ethnicity, and mode of prenatal diagnosis and compared with women with no prior spontaneous abortions, women with one prior spontaneous abortion (adjusted odds ratio [AOR] 1.21, 95% confidence interval [CI] 1.01-1.47) or 3 or more prior spontaneous abortions (AOR 1.51, 95% CI 1.02-2.25) had a statistically significant increase in aneuploidy in a subsequent pregnancy. Women with 2 prior spontaneous abortions had an AOR of 1.26 for aneuploidy, but the 95% CI contained unity. CONCLUSION An increased risk of karyotypic abnormality identified at the time of prenatal diagnosis is demonstrated in patients with an increasing number of spontaneous abortions. This study provides information regarding this risk among women presenting for prenatal diagnosis. According to our data, for a woman with an a priori risk of 1 in 300 for Down syndrome, 3 prior spontaneous abortions would increase that risk by 47% to 1 in 204. These results should be confirmed in low-risk populations.
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Affiliation(s)
- Katherine Bianco
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco, California 94143, USA.
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Weier JF, Weier HUG, Nureddin A, Pedersen RA, Racowsky C. Aneuploidy involving chromosome 1 in failed-fertilized human oocytes is unrelated to maternal age. J Assist Reprod Genet 2005; 22:285-93. [PMID: 16195825 DOI: 10.1007/s10815-005-5999-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2004] [Accepted: 03/14/2005] [Indexed: 11/28/2022] Open
Abstract
PURPOSE To study whether maternal meiotic errors in failed-fertilized oocytes involving chromosome 1 occur at frequencies similar to those involving other autosomes, and whether their frequency is affected by maternal age. METHODS Using fluorescence in situ hybridization (FISH), frequencies of aneusomy and chromatid pre-division involving chromosomes 1, 16, 18, and 21 were determined for 273 failed-fertilized oocytes. RESULTS The aneuploidy rate for chromosome 1 was 15.8%, and was neither age-dependent nor significantly different from that for chromosomes 16, 18 or 21. Only chromosome 16 exhibited an age-dependent increase in aneusomy rates. The frequency of chromatid pre-division was lower for chromosome 1 than for chromosome 18 (11.9% vs. 25.4%; p = 0.01), but not different from that for chromosomes 16 or 21. CONCLUSION Aneuploidy involving chromosome 1 in failed-fertilized oocytes is unrelated to maternal age and occurs at a frequency similar to that for chromosomes 16, 18, and 21.
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Affiliation(s)
- Jingly Fung Weier
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of California, San Francisco, USA.
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Lamb NE, Sherman SL, Hassold TJ. Effect of meiotic recombination on the production of aneuploid gametes in humans. Cytogenet Genome Res 2005; 111:250-5. [PMID: 16192701 DOI: 10.1159/000086896] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2005] [Accepted: 03/04/2005] [Indexed: 12/24/2022] Open
Abstract
Within the last decade, aberrant meiotic recombination has been confirmed as a molecular risk factor for chromosome nondisjunction in humans. Recombination tethers homologous chromosomes, linking and guiding them through proper segregation at meiosis I. In model organisms, mutations that disturb the recombination pathway increase the frequency of chromosome malsegregation and alterations in both the amount and placement of meiotic recombination are associated with nondisjunction. This association has been established for humans as well. Significant alterations in recombination have been found for all meiosis I-derived trisomies studied to date and a subset of so called "meiosis II" trisomy. Often exchange levels are reduced in a subset of cases where the nondisjoining chromosome fails to undergo recombination. For other trisomies, the placement of meiotic recombination has been altered. It appears that recombination too near the centromere or too far from the centromere imparts an increased risk for nondisjunction. Recent evidence from trisomy 21 also suggests an association may exist between recombination and maternal age, the most widely identified risk factor for aneuploidy. Among cases of maternal meiosis I-derived trisomy 21, increasing maternal age is associated with a decreasing frequency of recombination in the susceptible pericentromeric and telomeric regions. It is likely that multiple risk factors lead to nondisjunction, some age dependent and others age independent, some that act globally and others that are chromosome specific. Future studies are expected to shed new light on the timing and placement of recombination, providing additional clues to the link between altered recombination and chromosome nondisjunction.
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Affiliation(s)
- N E Lamb
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA.
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Lamb NE, Yu K, Shaffer J, Feingold E, Sherman SL. Association between maternal age and meiotic recombination for trisomy 21. Am J Hum Genet 2005; 76:91-9. [PMID: 15551222 PMCID: PMC1196437 DOI: 10.1086/427266] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2004] [Accepted: 11/08/2004] [Indexed: 11/03/2022] Open
Abstract
Altered genetic recombination has been identified as the first molecular correlate of chromosome nondisjunction in both humans and model organisms. Little evidence has emerged to link maternal age--long recognized as the primary risk factor for nondisjunction--with altered recombination, although some studies have provided hints of such a relationship. To determine whether an association does exist, chromosome 21 recombination patterns were examined in 400 trisomy 21 cases of maternal meiosis I origin, grouped by maternal age. These recombination patterns were used to predict the chromosome 21 exchange patterns established during meiosis I. There was no statistically significant association between age and overall rate of exchange. The placement of meiotic exchange, however, differed significantly among the age groups. Susceptible patterns (pericentromeric and telomeric exchanges) accounted for 34% of all exchanges among the youngest class of women but only 10% of those among the oldest class. The pattern of exchanges among the oldest age group mimicked the pattern observed among normally disjoining chromosomes 21. These results suggest that the greatest risk factor for nondisjunction among younger women is the presence of a susceptible exchange pattern. We hypothesize that environmental and age-related insults accumulate in the ovary as a woman ages, leading to malsegregation of oocytes with stable exchange patterns. It is this risk, due to recombination-independent factors, that would be most influenced by increasing age, leading to the observed maternal age effect.
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Affiliation(s)
- Neil E Lamb
- Department of Human Genetics, Emory University, 615 Michael Street, Atlanta, GA 30322, USA.
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17
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Yusuf RZ, Naeem R. Cytogenetic Abnormalities in Products of Conception: A Relationship Revisited. Am J Reprod Immunol 2004; 52:88-96. [PMID: 15214948 DOI: 10.1111/j.1600-0897.2004.00196.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVES Cytogenetic evaluation of product of conception (POC) is essential to determine the cause of pregnancy loss and aid the prenatal diagnosis of subsequent pregnancies. The purpose of this study is twofold. (1) To profile cytogenetic abnormalities, their relationship with maternal and gestational age and analyze sex ratios in our case series of 2052 consecutive samples of POC referred to the Baystate Medical Center, Laboratory Genetics between January 1992 and January 1999. (2) To present a comprehensive review of such data published in the last 15 years, in order to study temporal differences in the above parameters and make this information readily available for cytogeneticists and genetic counselors. MATERIALS AND METHODS Data was entered and analyzed in Epi Info version 6.0 using the Z-test, chi-square test of significance and linear correlation coefficient. RESULTS AND CONCLUSIONS The profile of cytogenetic abnormalities detected in POC has not changes significantly over time. The mean maternal age in our study (overall and for trisomies) was higher than that reported previously, which is consistent with the noted trend of increasing age at pregnancy in recent years. Our study provides evidence that abnormal karyotypes are aborted earlier and that tetraploidies have the least survival amongst all abnormalities. The higher mean gestational age for trisomic abortions in our study, as compared with previously reported figures, can be attributed to the increasing practice of active maternal screening with subsequent therapeutic abortions. Analysis of sex ratios may reaffirm a female specific developmental disadvantage in early stages of pregnancy.
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Affiliation(s)
- Rushdia Z Yusuf
- Baystate Medical Center, Department of Pathology, Tufts University School of Medicine, Springfield, MA, USA
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18
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Abstract
Aneuploidy (trisomy or monosomy) is the most commonly identified chromosome abnormality in humans, occurring in at least 5% of all clinically recognized pregnancies. Most aneuploid conceptuses perish in utero, which makes this the leading genetic cause of pregnancy loss. However, some aneuploid fetuses survive to term and, as a class, aneuploidy is the most common known cause of mental retardation. Despite the devastating clinical consequences of aneuploidy, relatively little is known of how trisomy and monosomy originate in humans. However, recent molecular and cytogenetic approaches are now beginning to shed light on the non-disjunctional processes that lead to aneuploidy.
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Affiliation(s)
- T Hassold
- Department of Genetics, Case Western Reserve University, 10,900 Euclid Avenue, Cleveland, Ohio 44106, USA.
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19
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Ford JH, Wilkin HZ, Thomas P, McCarthy C. A 13-year cytogenetic study of spontaneous abortion: clinical applications of testing. Aust N Z J Obstet Gynaecol 1996; 36:314-8. [PMID: 8883759 DOI: 10.1111/j.1479-828x.1996.tb02719.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Chromosome analysis was performed on 1,543 specimens of first trimester miscarriage received between 1982 and 1994. Comparisons with earlier studies show that some findings are absolutely consistent between different years and populations, but some major differences are also found. The results are considered in the light of several recent genetic, environmental and physiological studies. Trisomy 16, and probably trisomy 22, is entirely dependent on maternal age; other trisomies show both maternal age and other environmental or genetic effects. Monosomy X and mosaic aneuploidy arise postzygotically by chromosome loss, a normal control mechanism. Some trisomy, dipaternal triploidy and tetraploidy probably occur because of pre- or postovulatory 'overripeness'; either due to transient or chronic maternal conditions or delayed fertilization. Unbalanced structural abnormalities, most apparently of de novo origin, are markedly increased compared to earlier studies and are possibly due to paternal environmental exposures. It is concluded that when considering histories of abortion, studies of the chromosomes of the aborted products are much more informative and cost-effective than studies of parental bloods. Where available, studies of products should be undertaken for preference, but only by experienced and committed laboratories.
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Affiliation(s)
- J H Ford
- Genetic Consulting and Testing (G.C.A.T.) Pty Ltd, Hendon, South Australia
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20
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Eichenlaub-Ritter U. Parental age-related aneuploidy in human germ cells and offspring: a story of past and present. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 1996; 28:211-36. [PMID: 8908181 DOI: 10.1002/(sici)1098-2280(1996)28:3<211::aid-em6>3.0.co;2-g] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Parental age is the most important aetiological factor in trisomy formation in humans. Cytogenetic studies on germ cells reviewed here imply that (i) 2-4% sperm are aneuploid and 8.6% oocytes from IVF are hyperploid (ii) a paternal age effect may exist, and (iii) oocytes of aged women contain precociously separated chromatids in metaphase II. Trisomy data suggest that most aneuploidy is generated during meiosis I of oogenesis and is maternal age-dependent. Trisomy 18 is unique, originating mostly from maternal meiosis II errors. The extra gonosome in 47, XXY derives mostly from a paternal meiosis I error. Trisomy of individual chromosomes may remain low, linearly rise, or exponentially increase with advanced maternal age. Maternal age related trisomies involve achiasmatic and normochiasmate chromosomes, and chromosomes with disturbed recombination and distally located chiasmata. Hypotheses on the origin of the maternal age effect are critically reviewed. One model is presented that relates to altered cell cycle and protein phosphorylation in oocytes of aged mammals and accounts for most of the observed data in humans and in experimental studies. Aneuploidy may thus involve a predetermined component but is possibly also influenced by extrinsic factors reducing oocyte quality or depleting the oocyte pool precociously. Areas of future research are proposed to elucidate (i) the significance of early disturbances in the prenatal ovary, (ii) parameters diminishing the quality of oocytes in dictyate stage, and (iii) mechanisms enabling oocytes to process all chromosomal configurations successfully during later stages of oogenesis. Studies with newly developed and existing animal models appear indispensable to identify exposures affecting chromosome disjunction during meiosis, especially in the aging female.
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21
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Warburton D, Kinney A. Chromosomal differences in susceptibility to meiotic aneuploidy. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 1996; 28:237-47. [PMID: 8908182 DOI: 10.1002/(sici)1098-2280(1996)28:3<237::aid-em7>3.0.co;2-a] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A basic question concerning the origins of germ cell aneuploidy is whether the same mechanisms operate for all chromosomes, or whether there are chromosome-specific factors influencing the susceptibility to nondisjunction. Although selective loss of some trisomies in early gestation may contribute to the observed differences in trisomy frequency, data from spontaneous abortions, early embryos and gametes strongly suggest that there are real differences in the frequency with which different trisomies arise. In particular the preponderance of trisomy 16 and acrocentric trisomy appears to be present at conception. Maternal and paternal age relationships also differ among trisomies, as do the extent of maternal and paternal contributions, and the relative frequency of meiosis I and meiosis II errors. Recombination patterns associated with nondisjunction also show chromosomal differences. Chromosomal differences in length, centromere position, pericentromeric and other repetitive sequences, recombination patterns and chromatin characteristics might all be related to a differential susceptibility to aneuploidy, but no current explanation accounts for the excess of maternally derived trisomy 16. The existence of chromosome-specific factors makes extrapolation from observations on one chromosome to all aneuploidy unwise, both for investigations into the causes of aneuploidy, and for surveillance of aneuploidy frequency.
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Affiliation(s)
- D Warburton
- Department of Genetics and Development, College of Physicians and Surgeons, Columbia University, New York, New York, USA
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22
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Affiliation(s)
- P A Jacobs
- Wessex Regional Genetics Laboratory, Salisbury District Hospital, United Kingdom
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23
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Griffin DK. Fluorescent in situ hybridization for the diagnosis of genetic disease at postnatal, prenatal, and preimplantation stages. INTERNATIONAL REVIEW OF CYTOLOGY 1994; 153:1-40. [PMID: 8045699 DOI: 10.1016/s0074-7696(08)62187-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- D K Griffin
- Department of Genetics and Biometry, University College London, United Kingdom
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24
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Abstract
Molecular studies conducted over the past year have demonstrated the importance of aberrant genetic recombination in the etiology of several human trisomies, and have begun to shed light on the basis of the association between advancing maternal age and trisomy. Preliminary studies of gametes using fluorescence in situ hybridization indicate that this will be a useful approach in the analysis of human non-disjunction.
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Affiliation(s)
- T Hassold
- Department of Genetics, Case Western Reserve University, Cleveland, Ohio 44106
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25
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Abstract
A new method is proposed for the surveillance of Down's syndrome among newborn. Despite the strong dependence of overall risk of Down's syndrome on maternal age, it has been suggested that an environmentally induced increase in risk may be additive over all maternal ages. The surveillance method introduced here is specifically designed to detect such changes. The method is based on registry data for successive periods for a given population. It is assumed that the number of Down's syndrome cases as well as the total number of births are known in all maternal age groups. Tables of average run lengths until an alarm (ARLs) are calculated for a total sample size of 14,500 in each period, the approximate number of births in a three-month period in Norway. Comparison with the Poisson cusum shows that the new surveillance method can detect moderate additive increases significantly faster. Applied retrospectively to quarterly data from the Medical Birth Registry of Norway for 1978-89, the proposed method was close to an alarm in 1985 and actually signalled a strong alarm in 1986, reflecting a previously reported increase in risk in this period. The cusum method was not so sensitive to the aberration in Down's syndrome risks in 1985 and 1986.
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Affiliation(s)
- R T Lie
- Medical Birth Registry of Norway, University of Bergen, Haukeland Hospital
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26
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Abstract
Previously proposed mechanisms for Down syndrome (trisomy 21) have generally invoked a progressive increase in meiotic nondisjunction to explain maternal-age dependence, but models of this sort have failed to predict the observed patterns of marker segregation. Here we propose instead that age-dependent trisomy 21 results primarily from a mechanism that favors maturation and utilization of euploid oocytes in preference to the pre-existing aneuploid products of mitotic (premeiotic) nondisjunction. The increased utilization of aneuploid oocytes at later stages of maternal life would result from their increased proportion following many progressive cycles of selection against their maturation in earlier stages. Derivation of a quantitative model and evaluation of existing data indicate that the pattern of marker segregation associated with age-dependent trisomy 21 supports the proposed mechanism.
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Affiliation(s)
- C J Zheng
- Department of Epidemiology, University of Washington, Seattle 98195
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27
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Hassold TJ, Pettay D, Freeman SB, Grantham M, Takaesu N. Molecular studies of non-disjunction in trisomy 16. J Med Genet 1991; 28:159-62. [PMID: 2051452 PMCID: PMC1016797 DOI: 10.1136/jmg.28.3.159] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The origin of the additional chromosome in 26 trisomy 16 spontaneous abortions was studied using DNA probes for chromosome 16, including a probe for centromeric alpha sequences. We were able to determine the parent and meiotic stage of origin of trisomy in 22 cases, with all being attributable to maternal meiosis I non-disjunction. Furthermore, in each of the remaining four cases the results were compatible with this origin. Thus, it is likely that the high incidence of trisomy 16 results from an abnormal process acting at maternal meiosis I which more frequently involves chromosome 16 than other similar sized chromosomes. In studies of recombination, we found little evidence for an association between reduced or absent recombination and chromosome 16 non-disjunction; however, we were unable to rule out an effect of hyperrecombination.
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Affiliation(s)
- T J Hassold
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia 30322
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28
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Lie RT, Heuch I, Irgens LM. A temporary increase of Down syndrome among births of young mothers in Norway: an effect of risk unrelated to maternal age? Genet Epidemiol 1991; 8:217-30. [PMID: 1836771 DOI: 10.1002/gepi.1370080403] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The Medical Birth Registry of Norway carries out a population-based surveillance of birth defects on a routine basis. An increased proportion of newborn with Down syndrome was seen among children of young mothers during 1985-1986. Three alternative explanations were considered: a first representing a maternal age specific effect, a second based on a general increase in a subgroup of cases caused by factors not related to maternal age, and a third based on the assumption that a particular birth cohort of young women was carrying a high risk. As 1987 and 1988 showed very low proportions in all age groups, the last explanation was considered less likely. Statistical modeling was used to explore which of the two remaining explanations of the temporary increase was the more likely. The observed changes were compatible with a change in the occurrence of a group of maternal age-independent Down syndrome cases, from 4.59 per 10,000 in 1973-1984 and again in 1987-1988 to a temporary high of 7.68 per 10,000 in 1985-1986. However, the possibility of an age specific change only among young mothers could not be ruled out.
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Affiliation(s)
- R T Lie
- Medical Birth Registry of Norway, Haukeland Hospital, Bergen
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29
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Bartels I, Hansmann I, Eiben B. Excess of females in chromosomally normal spontaneous abortuses. AMERICAN JOURNAL OF MEDICAL GENETICS 1990; 35:297-8. [PMID: 2309776 DOI: 10.1002/ajmg.1320350235] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- I Bartels
- Institut für Humangenetik, Universität Göttingen, Federal Republic of Germany
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30
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Tharapel AT, Elias S, Shulman LP, Seely L, Emerson DS, Simpson JL. Resorbed co-twin as an explanation for discrepant chorionic villus results: non-mosaic 47,XX,+16 in villi (direct and culture) with normal (46,XX) amniotic fluid and neonatal blood. Prenat Diagn 1989; 9:467-72. [PMID: 2771885 DOI: 10.1002/pd.1970090703] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Non-mosaic trisomy 16 was observed in chorionic villus cytotrophoblasts (direct) as well as cultured mesenchymal core cells derived from the pregnancy of a 38-year-old woman. Chromosome preparations from amniotic fluid and neonatal cultures (cord blood) were 46,XX. Normal fetal growth as determined by serial ultrasound examinations occurred throughout the pregnancy, which resulted in a healthy 2724 g female. Multiple biopsies taken from the umbilical cord, placental cotyledons, and fetal membranes were 46,XX. However, a placental nodule and three of six cultures initiated from membranes (amnion and chorion) showed 46,XX/47,XX,+16 mosaicism. We propose that the trisomy 16 cells arose from residual villi derived from a trisomic co-twin that never developed. This case further demonstrates that normal fetal growth may presage normal outcome irrespective of cytogenetic findings in cytotrophoblasts (direct) and cultured mesenchymal core cells.
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Affiliation(s)
- A T Tharapel
- Department of Pediatrics, University of Tennessee, Memphis 38163
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