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van Dongen J, Hubers N, Boomsma DI. New insights into the (epi)genetics of twinning. Hum Reprod 2024; 39:35-42. [PMID: 38052159 PMCID: PMC10767898 DOI: 10.1093/humrep/dead131] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 05/24/2023] [Indexed: 12/07/2023] Open
Abstract
Spontaneous dizygotic (DZ) twins, i.e. twins conceived without the use of ARTs, run in families and their prevalence varies widely around the globe. In contrast, monozygotic (MZ) twins occur at a constant rate across time and geographical regions and, with some rare exceptions, do not cluster in families. The leading hypothesis for MZ twins, which arise when a zygote splits during preimplantation stages of development, is random occurrence. We have found the first series of genes underlying the liability of being the mother of DZ twins and have shown that being an MZ twin is strongly associated with a stable DNA methylation signature in child and adult somatic tissues. Because identical twins keep this molecular signature across the lifespan, this discovery opens up completely new possibilities for the retrospective diagnosis of whether a person is an MZ twin whose co-twin may have vanished in the early stages of pregnancy. Here, we summarize the gene finding results for mothers of DZ twins based on genetic association studies followed by meta-analysis, and further present the striking epigenetic results for MZ twins.
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Affiliation(s)
- Jenny van Dongen
- Netherlands Twin Register, Department of Biological Psychology, Amsterdam Reproduction and Development Research Institute, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Nikki Hubers
- Netherlands Twin Register, Department of Biological Psychology, Amsterdam Reproduction and Development Research Institute, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Dorret I Boomsma
- Netherlands Twin Register, Department of Biological Psychology, Amsterdam Reproduction and Development Research Institute, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
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Zhou Y, Crider KS, Yeung LF, Rose CE, Li Z, Berry RJ, Li S, Moore CA. Periconceptional folic acid use prevents both rare and common neural tube defects in China. Birth Defects Res 2022; 114:184-196. [PMID: 35098705 PMCID: PMC11091954 DOI: 10.1002/bdr2.1983] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 01/14/2022] [Accepted: 01/16/2022] [Indexed: 12/23/2022]
Abstract
BACKGROUND Neural tube defects (NTDs) encompass a variety of distinct types. We assessed if the preventive effect of folic acid (FA) varied by NTD type and infant sex. METHODS We examined all pregnancies with NTD status confirmation from a pregnancy-monitoring system in selected locations in northern and southern regions of China between 1993 and 1996. Women who took 400 μg of FA daily during 42 days after last menstrual period were considered FA users. We analyzed NTD prevalence by FA use status, NTD type, geographic region, and infant sex. RESULTS Among 626,042 pregnancies, 700 were affected by an NTD. Among FA nonusers, 65 pregnancies (8.8 per 10,000) in the north and 51 pregnancies (1.2 per 10,000) in the south were affected by one of the two rare NTDs, that is, craniorachischisis, iniencephaly. FA use prevented occurrence of these two rare NTDs and reduced the prevalence of spina bifida (SB) by 78% (from 17.9 to 3.9 per 10,000) in the north and 51% (from 2.4 to 1.2 per 10,000) in the south. Among FA users, SB prevalence, including SB with high lesion level, was significantly reduced in both geographic regions. FA use reduced prevalence of anencephaly and encephalocele by 85% and 50%, respectively in the north, while it did not reduce the prevalence of these two NTDs in the south. There was a greater reduction in NTD prevalence in female than in male infants and fetuses. CONCLUSIONS This is the first study to show that FA prevents the entire spectrum of NTD types.
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Affiliation(s)
- Ying Zhou
- National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Krista S. Crider
- National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Lorraine F. Yeung
- National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Charles E. Rose
- National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Zhu Li
- Institute of Reproductive and Child Health, School of Public Health, Peking University, Beijing, China
| | - Robert J. Berry
- National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Song Li
- Peking University Third Hospital, Beijing, China
| | - Cynthia A. Moore
- National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
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Examining the Vanishing Twin Hypothesis of Neural Tube Defects: Application of an Epigenetic Predictor for Monozygotic Twinning. Twin Res Hum Genet 2021; 24:155-159. [PMID: 34308812 DOI: 10.1017/thg.2021.25] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Strong associations between neural tube defects (NTDs) and monozygotic (MZ) twinning have long been noted, and it has been suggested that NTD cases who do not present as MZ twins may be the survivors of MZ twinning events. We have recently shown that MZ twins carry a strong, distinctive DNA methylation signature and have developed an algorithm based on genomewide DNA methylation array data that distinguishes MZ twins from dizygotic twins and other relatives at well above chance level. We have applied this algorithm to published methylation data from five fetal tissues (placental chorionic villi, kidney, spinal cord, brain and muscle) collected from spina bifida cases (n = 22), anencephalic cases (n = 15) and controls (n = 19). We see no difference in signature between cases and controls, providing no support for a common etiological role of MZ twinning in NTDs. The strong associations therefore continue to await elucidation.
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Douglas Wilson R, Van Mieghem T, Langlois S, Church P. Guideline No. 410: Prevention, Screening, Diagnosis, and Pregnancy Management for Fetal Neural Tube Defects. JOURNAL OF OBSTETRICS AND GYNAECOLOGY CANADA 2020; 43:124-139.e8. [PMID: 33212246 DOI: 10.1016/j.jogc.2020.11.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
OBJECTIVE This revised guideline is intended to provide an update on the genetic aspects, prevention, screening, diagnosis, and management of fetal neural tube defects. TARGET POPULATION Women who are pregnant or may become pregnant. Neural tube defect screening should be offered to all pregnant women. OPTIONS For prevention: a folate-rich diet, and folic acid and vitamin B12 supplementation, with dosage depending on risk level. For screening: second-trimester anatomical sonography; first-trimester sonographic screening; maternal serum alpha fetoprotein; prenatal magnetic resonance imaging. For genetic testing: diagnostic amniocentesis with chromosomal microarray and amniotic fluid alpha fetoprotein and acetylcholinesterase; fetal exome sequencing. For pregnancy management: prenatal surgical repair; postnatal surgical repair; pregnancy termination with autopsy. For subsequent pregnancies: prevention and screening options and counselling. OUTCOMES The research on and implementation of fetal surgery for prenatally diagnosed myelomeningocele has added a significant treatment option to the previous options (postnatal repair or pregnancy termination), but this new option carries an increased risk of maternal morbidity. Significant improvements in health and quality of life, both for the mother and the infant, have been shown to result from the prevention, screening, diagnosis, and treatment of fetal neural tube defects. BENEFITS, HARMS, AND COSTS The benefits for patient autonomy and decision-making are provided in the guideline. Harms include an unexpected fetal diagnosis and the subsequent management decisions. Harm can also result if the patient declines routine sonographic scans or if counselling and access to care for neural tube defects are delayed. Cost analysis (personal, family, health care) is not within the scope of this clinical practice guideline. EVIDENCE A directed and focused literature review was conducted using the search terms spina bifida, neural tube defect, myelomeningocele, prenatal diagnosis, fetal surgery, neural tube defect prevention, neural tube defect screening, neural tube defect diagnosis, and neural tube defect management in order to update and revise this guideline. A peer review process was used for content validation and clarity, with appropriate ethical considerations. VALIDATION METHODS The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations). INTENDED AUDIENCE Maternity care professionals who provide any part of pre-conception, antenatal, delivery, and neonatal care. This guideline is also appropriate for patient education. RECOMMENDATIONS (GRADE RATINGS IN PARENTHESES).
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Douglas Wilson R, Van Mieghem T, Langlois S, Church P. Directive clinique n o 410 : Anomalies du tube neural : Prévention, dépistage, diagnostic et prise en charge de la grossesse. JOURNAL OF OBSTETRICS AND GYNAECOLOGY CANADA 2020; 43:140-157.e8. [PMID: 33212245 DOI: 10.1016/j.jogc.2020.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
OBJECTIF La présente directive clinique révisée vise à fournir une mise à jour sur les aspects génétiques, la prévention, le dépistage, le diagnostic et la prise en charge des anomalies du tube neural. POPULATION CIBLE Les femmes enceintes ou qui pourraient le devenir. Il convient d'offrir le dépistage des anomalies du tube neural à toutes les femmes enceintes. OPTIONS Pour la prévention : un régime alimentaire riche en acide folique et des suppléments d'acide folique et de vitamine B12 selon une posologie d'après le niveau de risque. Pour le dépistage : l'échographie obstétricale du deuxième trimestre, le dépistage échographique du premier trimestre, le dosage de l'alphafœtoprotéine sérique maternelle et l'imagerie par résonance magnétique prénatale. Pour les tests génétiques : l'amniocentèse diagnostique avec analyse chromosomique sur micropuce et le dosage de l'alphafœtoprotéine et de l'acétylcholinestérase dans le liquide amniotique et le séquençage de l'exome fœtal. Pour la prise en charge de la grossesse : la réparation chirurgicale prénatale, la réparation chirurgicale postnatale et l'interruption de grossesse avec autopsie. Pour les grossesses subséquentes : les options de prévention et de dépistage et les conseils. RéSULTATS: La recherche et la mise en œuvre du traitement chirurgical fœtal en cas de diagnostic prénatal de myéloméningocèle ont ajouté une option thérapeutique fœtale importante aux options précédentes (réparation postnatale ou interruption de grossesse), mais cette nouvelle option comporte un risque accru de morbidité maternelle. La prévention, le dépistage, le diagnostic et le traitement des anomalies du tube neural se révèlent entraîner des améliorations importantes à la mère et au nourrisson en matière de santé et de qualité de vie. BéNéFICES, RISQUES ET COûTS: Le type et l'ampleur des bénéfices, risques et coûts attendus pour les patientes grâce à la mise en œuvre de la présente directive clinique par un établissement de soins de santé intègrent un canal maternel préconception et prénatal adéquat comprenant l'accès des patientes aux soins, les conseils, les analyses et examens, l'imagerie, le diagnostic et l'interprétation. Les bénéfices relatifs à l'autonomie de la patiente et au processus décisionnel sont énoncés dans la présente directive clinique. Les risques comprennent un diagnostic fœtal inattendu et les décisions de prise en charge subséquentes. Le fait que la patiente refuse les échographies habituelles et le retard du conseil ou d'accès aux soins en cas d'anomalie du tube neural comportent également des risques. L'analyse des coûts (personnels, familiaux, santé publique) ne fait pas partie de la portée de la présente directive clinique. DONNéES PROBANTES: Afin de mettre à jour et réviser la présente directive, une revue de la littérature ciblée et dirigée a été effectuée à l'aide des termes de recherche suivants : spina bifida, neural tube defect, myelomeningocele, prenatal diagnosis, fetal surgery, neural tube defect prevention, neural tube defect screening, neural tube defect diagnosis et neural tube defect management. Un processus d'examen par les pairs a été utilisé pour la validation et la clarté du contenu, avec des considérations appropriées d'ordre éthique. MéTHODES DE VALIDATION: Les auteurs ont évalué la qualité des données probantes et la force des recommandations en utilisant l'approche d'évaluation, de développement et d'évaluation (GRADE). Consulter l'annexe A en ligne (le tableau A1 pour les définitions et le tableau A2 pour les interprétations des recommandations fortes et faibles). PROFESSIONNELS CONCERNéS: Professionnels des soins de maternité qui offrent des soins préconception, prénataux, obstétricaux ou néonataux. La présente directive clinique convient également aux fins d'éducation des patientes. RECOMMANDATIONS (CLASSEMENT GRADE ENTRE PARENTHèSES).
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Kobets A, Lee RP, Oriko D, Jackson E, Robinson S, Cohen A, Groves ML. Dual Myelomeningoceles in Twins: Case Report, Review, and Insights for Etiology. Pediatr Neurosurg 2020; 55:363-373. [PMID: 33264792 DOI: 10.1159/000511365] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 09/03/2020] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Despite folate supplementation, neural tube defects (NTDs) still occur in 0.5-1.0/1,000 pregnancies, with 30-50% not preventable with folate. Twinning has increased due to artificial fertilization and in itself predisposes to NTDs at a rate of 1.6/1,000. The contributions of genetic and environmental factors to myelomeningocele development remain poorly understood. Expression patterns of congenital pathologies in twins can sometimes provide etiological insight. Concordance of NTDs in twins is 0.03/1,000, with dual myelomeningocele reported in only 23 pairs, only one of which survived. We present the 24th pair, the 1st to maintain lower extremity motor function. We review all prior cases and discuss implications of twin concordance on the interplay of genetic and environmental influences. Case Report and Review: A new case of female monozygotic twins born to a well-nourished 24-year-old female is reported with details of perioperative care. Prenatal ultrasound showed L3-S4 and L5-S4 myelomeningoceles, Chiari II malformations, and ventriculomegaly. Copy number microarray was unrevealing. Each underwent uncomplicated repair on day of life 1, and ventriculoperitoneal shunt placement on days of life 10 and 16. Both had movement in the legs upon 6-week follow-up. All prior reported cases of concordant twin myelomeningoceles were abstracted and analyzed, revealing persistence of occurrence despite folate supplementation and a majority occurring in dizygotic pairs. The literature is also reviewed to summarize current knowledge of myelomeningocele pathophysiology as it relates to genetic and environmental influences. DISCUSSION Meticulous surgical and perioperative care allowed for early positive outcomes in each twin. However, etiopathogenesis remains elusive. In general, only of a minority of cases have underlying genetic lesions or clear environmental triggers. Concordance in monozygotic twins argues for a strong genetic influence; yet, literature review reveals a higher rate of concordant dizygotic twins. This, along with the observation of differing resultant phenotypes in monozygotic twins as seen in this case, prompts further investigation into nonfolate environmental influences. While efforts in genetic investigation should continue, the role of teratogens and exposures should not be minimized in research efforts, public health, and family counseling. Clinical genetic testing remains of limited utility in the majority of patients until more is known.
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Affiliation(s)
- Andrew Kobets
- Division of Pediatric Neurosurgery, Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ryan P Lee
- Division of Pediatric Neurosurgery, Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA,
| | - David Oriko
- Division of Pediatric Neurosurgery, Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Eric Jackson
- Division of Pediatric Neurosurgery, Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Shenandoah Robinson
- Division of Pediatric Neurosurgery, Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Alan Cohen
- Division of Pediatric Neurosurgery, Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Mari L Groves
- Division of Pediatric Neurosurgery, Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Auffret M, Cottin J, Vial T, Cucherat M. Clomiphene citrate and neural tube defects: a meta‐analysis of controlled observational studies. BJOG 2019; 126:1127-1133. [DOI: 10.1111/1471-0528.15800] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2019] [Indexed: 01/19/2023]
Affiliation(s)
- M Auffret
- Service Hospitalo‐Universitaire de Pharmaco‐Toxicologie Hospices Civils de Lyon Lyon France
| | - J Cottin
- Service Hospitalo‐Universitaire de Pharmaco‐Toxicologie Hospices Civils de Lyon Lyon France
| | - T Vial
- Service Hospitalo‐Universitaire de Pharmaco‐Toxicologie Hospices Civils de Lyon Lyon France
| | - M Cucherat
- Service Hospitalo‐Universitaire de Pharmaco‐Toxicologie Hospices Civils de Lyon Lyon France
- Laboratoire de Biométrie & Biologie Evolutive Département Biostatistiques & Modélisation pour la Santé et l'Environnement Equipe Evaluation et Modélisation des Effets des Médicaments CNRS – Université Lyon 1 – UMR5558 Lyon France
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Stricker S, Balmer C, Guzman R, Soleman J. Dizygotic opposite-sex twins with surgically repaired concordant myelomeningocele conceived by in vitro fertilization using intracytoplasmic sperm injection: a case report and review of the literature. Childs Nerv Syst 2019; 35:725-728. [PMID: 30349985 DOI: 10.1007/s00381-018-3990-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 10/10/2018] [Indexed: 11/24/2022]
Abstract
BACKGROUND Myelomeningocele (MMC) is a common subtype of congenital neural tube defects (NTD). Although congenital malformations including NTD are more common in twins, concordance, especially in dizygotic twins, is extremely rare and is found mostly in same-sex twins. The role of genetic and environmental factors in the etiology of MMC is unclear. CASE REPORT Dizygotic twins of opposite sex were born at term to a 35-year-old woman conceived with in vitro fertilization (IVF) using intracytoplasmic sperm injection (ICSI). Prenatal ultrasonography (US) revealed concordant lumbosacral MMC at 18 weeks of gestation as well as ventriculomegaly and Arnold-Chiari malformation type II at 28 weeks. Both twins underwent surgical repair of the MMC within 48 h after birth and required a ventriculoperitoneal shunt in the second week of life. DISCUSSION The case presented raises questions concerning the etiology of MMC, since in twins, it is compelling to attribute the etiology to genetic factors. In the literature, 22 pairs of twins with concordant MMC have been reported, and of the 10 dizygotic twins described, four were of opposite sex. However, in monozygotic twins, most of the cases are non-concordant; therefore, the role of genetics remains unclear. In addition, environmental factors such as nutrition, metabolic folic acid deficiency, and assisted conception with IVF and ICSI might play a role as well. CONCLUSION The appearance of concordant MMC in opposite-sex dizygotic twins, conceived by IVF using ICSI, intrigues questions concerning the etiology of MMC. In such cases, genetic counseling and evaluation should be considered.
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Affiliation(s)
- Sarah Stricker
- Department of Neurosurgery, Division of Pediatric Neurosurgery, University Hospital and Children's Hospital of Basel, Spitalstrasse 21, 4031, Basel, Switzerland
| | - Cécile Balmer
- Department of Pediatric Surgery, University Children's Hospital of Basel, Basel, Switzerland
| | - Raphael Guzman
- Department of Neurosurgery, Division of Pediatric Neurosurgery, University Hospital and Children's Hospital of Basel, Spitalstrasse 21, 4031, Basel, Switzerland
| | - Jehuda Soleman
- Department of Neurosurgery, Division of Pediatric Neurosurgery, University Hospital and Children's Hospital of Basel, Spitalstrasse 21, 4031, Basel, Switzerland.
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Poletta FA, Rittler M, Saleme C, Campaña H, Gili JA, Pawluk MS, Gimenez LG, Cosentino VR, Castilla EE, López-Camelo JS. Neural tube defects: Sex ratio changes after fortification with folic acid. PLoS One 2018. [PMID: 29538416 PMCID: PMC5851584 DOI: 10.1371/journal.pone.0193127] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Background Historically, neural tube defects (NTDs) have predominated in female infants but the reasons remain unclear. In South America, the pre- folic acid fortification (FAF) rates of NTDs were around 18/10,000 births for females and 12/10,000 births for males, with an estimated sex ratio (male/female) of 0.67. During the post- FAF period, unpublished routine reports have indicated changes in the sex ratio for these defects while some descriptive reports are controversial. To date and to our knowledge, however, no studies specifically focusing on these changes to test this hypothesis directly have been undertaken. The aim of this study was to analyze changes in the sex ratio of infants with NTDs after FAF in South American countries. Materials and methods With a descriptive cross-sectional study design, 2,597 infants with isolated NTDs born between 1990 and 2013 in 3 countries participating in the Latin American Collaborative Study of Congenital Malformations (ECLAMC) network were included: (Chile N = 521 and Argentina N = 1,619 [with FAF policies]; Venezuela N = 457 [without FAF policies; used as control]; total births = 2,229,561). The differences-in-differences method and Poisson regressions were used to evaluate the sex ratio shift from female to male before vs. after FAF, and to assess whether these differences were related to the fortification. Results and conclusions In Chile and Argentina the prevalence of NTDs, particularly anencephaly and cervico-thoracic spina bifida, showed a greater reduction rate in females than in males after FAF, resulting in a change of the sex ratio of infants with NTDs. Some mechanisms possibly involved in this differential reduction are proposed which might be useful to identify the pathogenesis of NTDs as a whole and specifically of those susceptible to the protective effect of folic acid.
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Affiliation(s)
- Fernando A. Poletta
- Latin American Collaborative Study of Congenital Malformations (ECLAMC) at Center for Medical Education and Clinical Research (CEMIC-CONICET), Buenos Aires, Argentina
- ECLAMC at INAGEMP (National Institute of Population Medical Genetics), Rio de Janeiro, Brazil
| | - Monica Rittler
- ECLAMC at Hospital Materno Infantil Ramón Sardá, University of Buenos Aires, Buenos Aires, Argentina
| | - Cesar Saleme
- ECLAMC at Maternity Hospital Nuestra Señora de las Mercedes, Tucumán, Argentina
| | - Hebe Campaña
- Latin American Collaborative Study of Congenital Malformations (ECLAMC) at Center for Medical Education and Clinical Research (CEMIC-CONICET), Buenos Aires, Argentina
| | - Juan A. Gili
- Latin American Collaborative Study of Congenital Malformations (ECLAMC) at Center for Medical Education and Clinical Research (CEMIC-CONICET), Buenos Aires, Argentina
| | - Mariela S. Pawluk
- Latin American Collaborative Study of Congenital Malformations (ECLAMC) at Center for Medical Education and Clinical Research (CEMIC-CONICET), Buenos Aires, Argentina
| | - Lucas G. Gimenez
- Latin American Collaborative Study of Congenital Malformations (ECLAMC) at Center for Medical Education and Clinical Research (CEMIC-CONICET), Buenos Aires, Argentina
| | - Viviana R. Cosentino
- Latin American Collaborative Study of Congenital Malformations (ECLAMC) at Center for Medical Education and Clinical Research (CEMIC-CONICET), Buenos Aires, Argentina
| | - Eduardo E. Castilla
- Latin American Collaborative Study of Congenital Malformations (ECLAMC) at Center for Medical Education and Clinical Research (CEMIC-CONICET), Buenos Aires, Argentina
- ECLAMC at INAGEMP (National Institute of Population Medical Genetics), Rio de Janeiro, Brazil
| | - Jorge S. López-Camelo
- Latin American Collaborative Study of Congenital Malformations (ECLAMC) at Center for Medical Education and Clinical Research (CEMIC-CONICET), Buenos Aires, Argentina
- ECLAMC at INAGEMP (National Institute of Population Medical Genetics), Rio de Janeiro, Brazil
- * E-mail:
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Karapetian MK. Discrete morphological variants of human cervical vertebrae: Exploring pattern of distribution and biological significance. HOMO-JOURNAL OF COMPARATIVE HUMAN BIOLOGY 2017; 68:176-198. [PMID: 28404241 DOI: 10.1016/j.jchb.2017.03.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 03/04/2017] [Indexed: 10/20/2022]
Abstract
Studies on discrete traits of the human cervical vertebrae, appearing at certain intervals during the last century, posed some questions regarding evolutionary processes that human cervical spine underwent during phylogenesis. To address questions of significance of these morphological traits we need first a good knowledge of the extent of their variation in modern humans. The aim of the current work was to integrate available data on the occurrence of various non-metric traits in the human cervical spine and search for the pattern of their distribution on intra- and inter-population levels. The study was based on data from five osteological samples from North America (Terry and Grant collections) and Russia (mid 20th c. and 18th c.); and data taken from literature. Traits were categorized into rare (<3%), low frequency (up to 10%), often encountered (10-30%) and characteristic for modern humans (>50% on average). Several traits showed mild to strong association with each other indicating interrelation between various spine characteristics. Of the traits analyzed, the following had consistent pattern of sex-related variability: complete dorsal ponticle, bifid spinous processes and cervical ribs; and ancestry-related variability: dorsal ponticle and bifid spinous processes. Each ancestry group (European, African, Asian and North American) had its specifics regarding the latter two traits which might be related to genetic isolation. Most of the traits, however, showed relatively similar pattern of distribution among various populations, including the pattern of within-spine variability. This suggests a common intraspecific pattern and a possible link to some fundamental characteristics of the human vertebral column.
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Affiliation(s)
- M K Karapetian
- Research Institute and Museum of Anthropology, Lomonosov Moscow State University, Moscow 125009, Russia.
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Melcer Y, Svirsky R, Vaknin Z, Levinsohn-Tavor O, Feldman N, Maymon R. Fetal abnormalities leading to termination of twin pregnancies: the 17-year experience of a single medical center. J Matern Fetal Neonatal Med 2016; 30:347-351. [DOI: 10.3109/14767058.2016.1173027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Yaakov Melcer
- Department of Obstetrics and Gynecology, Assaf Harofeh Medical Center, Zerifin, Israel
| | - Ran Svirsky
- Department of Obstetrics and Gynecology, Assaf Harofeh Medical Center, Zerifin, Israel
| | - Zvi Vaknin
- Department of Obstetrics and Gynecology, Assaf Harofeh Medical Center, Zerifin, Israel
| | - Orna Levinsohn-Tavor
- Department of Obstetrics and Gynecology, Assaf Harofeh Medical Center, Zerifin, Israel
| | - Noa Feldman
- Department of Obstetrics and Gynecology, Assaf Harofeh Medical Center, Zerifin, Israel
| | - Ron Maymon
- Department of Obstetrics and Gynecology, Assaf Harofeh Medical Center, Zerifin, Israel
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Pelizzari E, Valdez CM, Picetti JDS, da Cunha AC, Dietrich C, Fell PRK, Targa LV, Zen PRG, Rosa RFM. Characteristics of fetuses evaluated due to suspected anencephaly: a population-based cohort study in southern Brazil. SAO PAULO MED J 2015; 133:101-8. [PMID: 25789781 PMCID: PMC10496632 DOI: 10.1590/1516-3180.2013.8012608] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 11/22/2013] [Accepted: 08/26/2014] [Indexed: 11/21/2022] Open
Abstract
CONTEXT AND OBJECTIVE Anencephaly is considered to be the most common type of neural tube defect. Our aim was to assess the clinical and gestational features of a cohort of fetuses with suspected anencephaly. DESIGN AND SETTING Population-based retrospective cohort study in a referral hospital in southern Brazil. METHODS The sample consisted of fetuses referred due to suspected anencephaly, to the Fetal Medicine Service of Hospital Materno Infantil Presidente Vargas, between January 2005 and September 2013. Clinical, radiological, pathological and survival data were gathered. RESULTS Our sample was composed of 29 fetuses. The diagnosis of suspected anencephaly was made on average at 21.3 weeks of gestation. Seven fetuses had malformations that affected other organs, and these included oral clefts (n = 4) and congenital heart defects (n = 2). In 16 cases, there was termination of pregnancy (n = 12) or intrauterine death (n = 4). Regarding those who were born alive (n = 13), all of them died in the first week of life. After postnatal evaluation, the diagnosis of anencephaly was confirmed in 22 cases (75.9%). Other conditions included amniotic band disruption complex (6.9%), microhydranencephaly (6.9%), merocrania (3.4%) and holoprosencephaly (3.4%). CONCLUSIONS Different conditions involving the cranial vault may be confused with anencephaly, as seen in our sample. However, these conditions also seem to have a poor prognosis. It seems that folic acid supplementation is not being properly performed.
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Affiliation(s)
- Emanuele Pelizzari
- MD. Physician, Residency Program in Obstetrics and Gynecology, Hospital Materno Infantil Presidente Vargas (HMIPV), Porto Alegre, Rio Grande do Sul, Brazil.
| | - Carolina Melendez Valdez
- MD. Physician, Residency Program in Obstetrics and Gynecology, Hospital Materno Infantil Presidente Vargas (HMIPV), Porto Alegre, Rio Grande do Sul, Brazil.
| | - Jamile dos Santos Picetti
- MD. Physician, Residency Program in Fetal Medicine, Hospital Materno Infantil Presidente Vargas (HMIPV), Porto Alegre, Rio Grande do Sul, Brazil.
| | - André Campos da Cunha
- MD. Obstetrician, Fetal Medicine, Hospital Materno Infantil Presidente Vargas (HMIPV), Porto Alegre, Rio Grande do Sul, Brazil.
| | - Cristine Dietrich
- MD. Obstetrician, Fetal Medicine, Hospital Materno Infantil Presidente Vargas (HMIPV), Porto Alegre, Rio Grande do Sul, Brazil.
| | - Paulo Renato Krahl Fell
- MD. Obstetrician, Fetal Medicine, Hospital Materno Infantil Presidente Vargas (HMIPV), Porto Alegre, Rio Grande do Sul, Brazil.
| | - Luciano Vieira Targa
- MD. Pediatric Radiologist, Hospital Materno Infantil Presidente Vargas (HMIPV), Porto Alegre, Rio Grande do Sul, Brazil.
| | - Paulo Ricardo Gazzola Zen
- PhD. Adjunct Professor of Clinical Genetics and of the Postgraduate Program on Pathology, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), and Clinical Geneticist, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA) and Complexo Hospitalar Santa Casa de Porto Alegre (CHSCPA), Porto Alegre, Rio Grande do Sul, Brazil.
| | - Rafael Fabiano Machado Rosa
- PhD. Clinical Geneticist, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Complexo Hospitalar Santa Casa de Porto Alegre (CHSCPA) and Hospital Materno Infantil Presidente Vargas (HMIPV), Porto Alegre, Rio Grande do Sul, Brazil.
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Wertelecki W, Yevtushok L, Zymak-Zakutnia N, Wang B, Sosyniuk Z, Lapchenko S, Hobart HH. Blastopathies and microcephaly in a Chornobyl impacted region of Ukraine. Congenit Anom (Kyoto) 2014; 54:125-49. [PMID: 24666273 PMCID: PMC4233949 DOI: 10.1111/cga.12051] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 01/05/2014] [Indexed: 12/17/2022]
Abstract
This population-based descriptive epidemiology study demonstrates that rates of conjoined twins, teratomas, neural tube defects, microcephaly, and microphthalmia in the Rivne province of Ukraine are among the highest in Europe. The province is 200 km distant from the Chornobyl site and its northern half, a region known as Polissia, is significantly polluted by ionizing radiation. The rates of neural tube defects, microcephaly and microphthalmia in Polissia are statistically significantly higher than in the rest of the province. A survey of at-birth head size showed that values were statistically smaller in males and females born in one Polissia county than among neonates born in the capital city. These observations provide clues for confirmatory and cause-effect prospective investigations. The strength of this study stems from a reliance on international standards prevalent in Europe and a decade-long population-based surveillance of congenital malformations in two distinct large populations. The limitations of this study, as those of other descriptive epidemiology investigations, is that identified cause-effect associations require further assessment by specific prospective investigations designed to address specific teratogenic factors.
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Affiliation(s)
- Wladimir Wertelecki
- Department of Medical Genetics, College of Medicine, University of South AlabamaMobile, Alabama, USA
- OMNI-Net for Children International Charitable FundRivne, Rivne Province, Ukraine
| | - Lyubov Yevtushok
- OMNI-Net for Children International Charitable FundRivne, Rivne Province, Ukraine
- Rivne Regional Medical Diagnostic CenterRivne, Rivne Province, Ukraine
| | - Natalia Zymak-Zakutnia
- OMNI-Net for Children International Charitable FundRivne, Rivne Province, Ukraine
- Khmelnytsky Perinatal CenterKhmelnytsky, Khmelnytsky Province, Ukraine
| | - Bin Wang
- Department of Mathematics and Statisitcs, University of South AlabamaMobile, Alabama, USA
| | - Zoriana Sosyniuk
- OMNI-Net for Children International Charitable FundRivne, Rivne Province, Ukraine
- Rivne Regional Medical Diagnostic CenterRivne, Rivne Province, Ukraine
| | - Serhiy Lapchenko
- OMNI-Net for Children International Charitable FundRivne, Rivne Province, Ukraine
| | - Holly H Hobart
- Cyto-Genetics Laboratory, Department of Pathology, University of Mississippi Medical CenterJackson, Mississippi, USA
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Agrawal A, Sampley S. Spinal dysraphism: A challenge continued to be faced by neurosurgeons in developing countries. Asian J Neurosurg 2014; 9:68-71. [PMID: 25126121 PMCID: PMC4129580 DOI: 10.4103/1793-5482.136713] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVES The incidence of spinal dysraphism has significantly decreased over the last few decades, all over the world; however, still the incidence is much higher in developing countries with poor socioeconomic status. MATERIALS AND METHODS The present study includes all patients managed for spinal dysraphism over a period of one year (January 2011-December 2011). Details including demographics, antenatal care history, site and type of lesion, neurological examination, imaging finding, associated congenital anomalies, management offered, and outcome were recorded. RESULTS A total of 27 children were operated for spinal dysraphism during the study period (17 males and 11 females). Median age was 120 days (age range, 1 day to 6 years). Mothers of 15 children did not seek any regular antenatal checkup and only 13 mothers received folic acid supplementation during pregnancy. Fourteen children were delivered at home and 13 were at hospital. The most common site was lumbosacral region (67.8%). Seven patients had rupture of the sac at the time of presentation, one child had local infection, and four patients had hydrocephalus (requiring shunt before surgical repair). Two patients developed hydrocephalus at follow up, needing shunt surgery. The mean hospital stay was 7 days (range, 5 days to 31 days; median, 10 days). CONCLUSION Spinal dysraphism is still a major public health problem in developing countries. Management of patients with spinal dysraphism is complex and needs close coordination between pediatrician, neurologist, neurosurgeon, and rehabilitation experts. A large number of factors influence the outcome.
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Affiliation(s)
- Amit Agrawal
- Department of Neurosurgery, Narayna Medical College Hospital, Chinthareddypalem, Nellore, Andhra Pradesh, India
| | - Sunil Sampley
- Department of Surgery, MM Institute of Medical Sciences and Research, Mullana, Ambala, India
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Sokal R, Tata LJ, Fleming KM. Sex prevalence of major congenital anomalies in the United Kingdom: a national population-based study and international comparison meta-analysis. ACTA ACUST UNITED AC 2014; 100:79-91. [PMID: 24523198 PMCID: PMC4016755 DOI: 10.1002/bdra.23218] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 11/08/2013] [Accepted: 12/21/2013] [Indexed: 11/11/2022]
Abstract
Background The aim of this study was to assess sex differences in major congenital anomaly (CA) diagnoses within a national population sample; to examine the influence of sociodemographic and maternal factors on these risks; and to conduct a meta-analysis using estimates from other population-based studies. Methods We conducted a population-based study in a United Kingdom research database of prospectively collected primary care data (The Health Improvement Network) including children born 1990 to 2009 (n = 794,169) and identified major CA diagnoses using EUROCAT (European Surveillance of Congenital Anomalies) classification. Prevalence ratios (PR) were used to estimate the risk of CA in males compared with females for any CA, system-specific subgroups and specific CA diagnoses. In a subpopulation of children whose medical records were linked to their mothers', we assessed the effect of adjusting for sociodemographic and maternal factors on sex odds ratios. PRs were pooled with measures from previously published studies. Results The prevalence of any CA was 307/10,000 in males (95% CI, 302–313) and 243/10,000 in females (95% CI, 238–248). Overall the risk of any CA was 26% greater in males (PR (male: female) 1.26, 95% CI, 1.23–1.30) however there was considerable variation across specific diagnoses. The magnitude and direction of risk did not change for any specific CA upon adjustment for sociodemographic and maternal factors. Our PRs were highly consistent with those from previous studies. Conclusion The overall risk of CA is greater in males than females, although this masked substantial variation by specific diagnoses. Sociodemographic and maternal factors do not appear to affect these risks. Birth Defects Research (Part A) 100:79–91, 2014. © 2014 Wiley Periodicals, Inc.
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Affiliation(s)
- Rachel Sokal
- Division of Epidemiology and Public Health, University of Nottingham, Nottingham, United Kingdom
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Chen CP, Hwu YM, Chen CY, Su YN, Lin TH, Kuo YL, Chern SR, Wang W. Concordant myelomeningocele in dizygotic twins conceived by intracytoplasmic sperm injection, in vitro fertilization, and embryo transfer. Taiwan J Obstet Gynecol 2014; 52:611-2. [PMID: 24411057 DOI: 10.1016/j.tjog.2013.10.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 09/30/2013] [Indexed: 11/26/2022] Open
Affiliation(s)
- Chih-Ping Chen
- Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan; Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan; Department of Biotechnology, Asia University, Taichung, Taiwan; School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan; Institute of Clinical and Community Health Nursing, National Yang-Ming University, Taipei, Taiwan; Department of Obstetrics and Gynecology, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
| | - Yuh-Ming Hwu
- Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan
| | - Chen-Yu Chen
- Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan
| | - Yi-Ning Su
- Department of Obstetrics and Gynecology, School of Medicine, Taipei Medical University, Taipei, Taiwan; Dianthus Maternal Fetal Medicine Clinic, Taipei, Taiwan
| | - Tzu-Hung Lin
- Dianthus Maternal Fetal Medicine Clinic, Taipei, Taiwan
| | - Yu-Ling Kuo
- Department of Obstetrics and Gynecology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Schu-Rern Chern
- Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan
| | - Wayseen Wang
- Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan; Department of Bioengineering, Tatung University, Taipei, Taiwan
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Suazo J, Pardo R, Castillo S, Martin LM, Rojas F, Santos JL, Rotter K, Solar M, Tapia E. Family-based association study between SLC2A1, HK1, and LEPR polymorphisms with myelomeningocele in Chile. Reprod Sci 2013; 20:1207-14. [PMID: 23427181 DOI: 10.1177/1933719113477489] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Obese/diabetic mothers present a higher risk to develop offspring with myelomeningocele (MM), evidence supporting the role of energy homeostasis-related genes in neural tube defects. Using polymerase chain reaction-restriction fragment length polymorphism, we have genotyped SLC2A1, HK1, and LEPR single-nucleotide polymorphisms in 105 Chilean patients with MM and their parents in order to evaluate allele-phenotype associations by means of allele/haplotype transmission test (TDT) and parent-of-origin effects. We detected an undertransmission for the SLC2A1 haplotype T-A (rs710218-rs2229682; P = .040), which was not significant when only lower MM (90% of the cases) was analyzed. In addition, the leptin receptor rs1137100 G allele showed a significant increase in the risk of MM for maternal-derived alleles in the whole sample (2.43-fold; P = .038) and in lower MM (3.20-fold; P = .014). Our results support the role of genes involved in energy homeostasis in the risk of developing MM, thus sustaining the hypothesis of diverse pathways and genetic mechanisms acting in the expression of such birth defect.
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Affiliation(s)
- José Suazo
- 1Departmento de Nutrición, Diabetes y Metabolismo, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
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Jauniaux E, Ben-Ami I, Maymon R. Do assisted-reproduction twin pregnancies require additional antenatal care? Reprod Biomed Online 2013; 26:107-19. [DOI: 10.1016/j.rbmo.2012.11.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2012] [Revised: 11/06/2012] [Accepted: 11/07/2012] [Indexed: 10/27/2022]
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19
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Juriloff DM, Harris MJ. Hypothesis: the female excess in cranial neural tube defects reflects an epigenetic drag of the inactivating X chromosome on the molecular mechanisms of neural fold elevation. ACTA ACUST UNITED AC 2012; 94:849-55. [PMID: 22753363 DOI: 10.1002/bdra.23036] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 04/04/2012] [Accepted: 05/01/2012] [Indexed: 01/10/2023]
Abstract
Females have long been known to be in excess among cranial neural tube defect (NTD) cases. Up to two thirds of human anencephalics and mouse exencephalics from various genetic causes are female, but the cause of this female excess is unknown. It appears not to be attributable to gonadal hormones, developmental delay in females, or preferential death of affected males. Recent studies of the Trp53 mouse mutant showed that exencephaly susceptibility depends on the presence of two X chromosomes, not the absence of the Y. Over a decade ago, we hypothesized that the relevant difference between female and male mammalian embryos at the time of cranial neural tube closure is the fact that females methylate most of the DNA in the large inactive X chromosome after every cell division, reducing the methylation available for other needs in female cells. Recently, the Whitelaw laboratory identified several proteins in mice (Momme D genes) involved in epigenetic silencing and methylation and shared in the silencing of transgenes, retrotransposons, and the inactive-X, and suggested that the inactive-X acts as a "sink" for epigenetic silencing proteins. The "inactive-X sink" hypothesis can be used to suggest expected changes in sex ratio in cranial NTDs in response to various genetic or environmental alterations. We recommend that observation of sex ratio become a standard component of all NTD studies. We suggest that the female excess among cranial NTDs is an epigenetic phenomenon whose molecular investigation will produce insight into the mechanisms underlying NTDs.
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Affiliation(s)
- Diana M Juriloff
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
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20
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Ben-Ami I, Edel Y, Barel O, Vaknin Z, Herman A, Maymon R. Do assisted conception twins have an increased risk for anencephaly? Hum Reprod 2011; 26:3466-71. [PMID: 21984575 DOI: 10.1093/humrep/der326] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The incidence rates of anterior neural tube defects, anencephaly and encephalocele appear increased among twins compared with singletons. The current study aimed to evaluate whether the etiology of this phenomenon is related to twinning, assisted reproductive technology (ART), or both. METHODS The study cohort consisted of parturient women who were referred to our ultrasonography unit between January 1998 and December 2009 due to suspicion of severe fetal abnormality. The study cohort was divided into two subgroups based on mode of conception: spontaneous and ART (including IVF and ICSI). The subgroups were further subdivided into singleton and multiple pregnancies. We also compared pregnancies diagnosed with anencephaly in the study group to all live births in the Department of Obstetrics and Gynecology. RESULTS Anencephaly was diagnosed in 43 fetuses out of 1154 (3.7%) pregnancies diagnosed with severe fetal anomaly. Anencephaly was diagnosed in 9 out of 78 twin pregnancies (11.5%); of these, 8 of 45 (17.8%) were ART conceived and 1 of 33 (3%) spontaneously conceived. A significant correlation was found between twinning and anencephaly, with an odds ratio (OR) of 3.4 [confidence interval (CI) = 1.3-8.9, P= 0.011], while no significant correlation was found between ART and anencephaly. A significant correlation was found between anencephaly and the combination of ART conception and twinning (OR of 6.6, CI = 2.8-15.3, P< 0.01). Analyzing the distribution of pregnancies diagnosed with anencephaly in the study group compared with the total number of live births in the department revealed a significant correlation between twinning and anencephaly, with an OR of 11.4 (CI = 4.9-26.5, P< 0.01), with no significant correlation between ART and anencephaly. Among all live births, a significant correlation was found between anencephaly and the combination of ART conception and twinning (OR of 24.6, CI = 11.4-53.2, P< 0.01). CONCLUSIONS Our data suggest that twin pregnancies conceived by ART constitute a high-risk group for anencephaly, due to a possible synergistic effect of twinning and ART.
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Affiliation(s)
- I Ben-Ami
- Department of Obstetrics and Gynecology, Assaf Harofeh Medical Center, affiliated with Sackler School of Medicine, Tel-Aviv University, Zerifin 70300, Israel
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Tennant PWG, Samarasekera SD, Pless-Mulloli T, Rankin J. Sex differences in the prevalence of congenital anomalies: a population-based study. ACTA ACUST UNITED AC 2011; 91:894-901. [PMID: 21987467 DOI: 10.1002/bdra.22846] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2011] [Revised: 05/27/2011] [Accepted: 06/15/2011] [Indexed: 11/09/2022]
Abstract
BACKGROUND Limited data is available concerning the sex distribution of various congenital anomaly subtypes. This study investigated sex differences in the prevalence of congenital anomalies, overall and by subtype, using high quality population-based data from the North of England. METHODS Information on congenital anomalies occurring among singleton pregnancies during 1985-2003 were extracted from the Northern Congenital Abnormality Survey (NorCAS). Anomalies were categorized by groups, subtypes, and syndromes according to the European Surveillance of Congenital Anomalies guidelines. Relative risks (RRs) comparing the prevalences in males to that in females were calculated for a range of congenital anomaly subtypes. RESULTS A total of 12,795 eligible cases of congenital anomaly were identified during the study period, including 7019 (54.9%) males and 5776 (45.1%) females. Overall, male fetuses were significantly more prevalent in pregnancies affected by a congenital anomaly than female fetuses (RR, male vs. female = 1.15; 95% confidence interval [CI], 1.11-1.19), but there was significant heterogeneity between subtypes (p < 0.001). Forty-four of 110 (40%) unique subtypes were at least 40% more prevalent in males than females, with affected subtypes occurring across all major anomaly groups. Thirteen of 110 (12%) unique subtypes were at least 40% more prevalent in females than males, but the female-biased RR of a neural tube defect was less pronounced than previously reported (RR = 0.84; 95% CI, 0.73-0.95). CONCLUSION This study adds to the growing evidence of sex-specific differences in the prevalence of a wide range of congenital anomaly subtypes.
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Affiliation(s)
- Peter W G Tennant
- Institute of Health & Society, Baddiley-Clark Building, Newcastle University, England, United Kingdom
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Margaron FC, Poenaru D, Bransford R, Albright AL. Timing of ventriculoperitoneal shunt insertion following spina bifida closure in Kenya. Childs Nerv Syst 2010; 26:1523-8. [PMID: 20422197 DOI: 10.1007/s00381-010-1156-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Accepted: 04/08/2010] [Indexed: 11/28/2022]
Abstract
PURPOSE In Western medical centers, emphasis has been placed on simultaneous myelomeningocele closure and ventriculoperitoneal shunting for children with spina bifida (SB) and co-morbid hydrocephalus (HC). This is not practical in developing countries where patients present in a delayed fashion, many with open, dirty myelomeningoceles. The purpose of this study was to evaluate whether timing of shunting in relation to myelomeningocele closure affected shunt-related complications such as SB wound infection, shunt infection, and shunt malfunction. METHODS A retrospective analysis was undertaken of all SB patients undergoing ventriculoperitoneal shunting within 11 days following myelomeningocele closure at Kijabe Hospital between 1997 and August 2007. Data were collected from hospital records and analyzed in SPSS. RESULTS Over the study period there were 276 patients included. Eighteen patients were shunted prior to SB closure and 13 patients had simultaneous shunting and SB closure. Patients shunted prior to, simultaneously, or within the first 4 days after SB closure had a fivefold higher shunt infection rate (23%) than those shunted 5-10 days following SB closure (4.7%) (p < 0.0001). Shunt malfunctions were also significantly higher in the group shunted prior to back closure (33.3%) vs. those shunted simultaneously (15.4%) or within the first 10 days following SB closure (13.9%) (p = 0.0001). No difference was seen in these groups with regard to wound infections. No difference in shunt-related complications was observed between those shunted 5 to 10 days following back closure. CONCLUSIONS This study indicates that in developing countries, patients with SB who present in a delayed fashion but require shunting and have sterile CSF, should have their shunts inserted 5-10 days after SB closure.
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Abstract
OBJECTIVE One of the populations most exposed to chronic low-dose radiation from Chornobyl (Chernobyl in Russian) lives in Polissia, the region representing the northern half of Rivne Province (Oblast) in Ukraine. Here the patterns and population rates of malformations are reported and possible etiologic factors and regional contrasts are explored. PATIENTS AND METHODS Malformations, as defined by international standards, noted among all 96 438 births in Rivne between 2000 and 2006, were analyzed statistically. Contrasts of rates in Polissia compared with the rest of Rivne also were investigated. RESULTS The overall rate of neural tube defects in Rivne is among the highest in Europe (22.2 per 10,000 live births). The rates of conjoined twins and teratomas also seem to be elevated. In Polissia, the overall rates of neural tube defects are even higher (27.0 vs 18.3, respectively; odds ratio: 1.46 [95% confidence interval: 1.13-1.93]), and the rates of microcephaly and microphthalmia may also be elevated. CONCLUSIONS The malformation patterns observed suggest early disruptions of blastogenesis, manifesting as alterations of body axes, twinning, duplications, laterality, and midline formation. The results are sufficiently compelling to justify continuing and expanding this investigation of malformations in chronic low-dose radiation-impacted regions of Ukraine.
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Affiliation(s)
- Wladimir Wertelecki
- Medical Genetics and Pediatrics, University of South Alabama, Technology Research Park IV, Suite 220, 307 University Blvd N, Mobile, AL 36688, USA.
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Abstract
This review provides a brief description of folate use and folic acid metabolism in relation to neural tube defect (NTD) risk. First, a meta-analysis of reduction in NTD recurrence and occurrence risk with periconceptional folic acid supplementation is presented. Second, an overview of the complex folate metabolism is given. Third, SNPs for genes involved in folate and homocysteine metabolism that have been studied in relation to NTD riskare discussed. Fourth, the questions whether folate receptor autoantibodies or hampered methylation are mechanisms underlying NTDs are briefly discussed.
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Affiliation(s)
- Henk J Blom
- Metabolic Unit, Department of Clinical Chemistry, Free University Medical Center Amsterdam, Amsterdam, The Netherlands.
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Abstract
Central nervous system maldevelopment can have different presentations in twins. We report on a case of different presentations of spina bifida occulta in monozygotic twins. The first twin presented at birth with a lipomyelomeningocele; a tethered cord was diagnosed in the second twin at 2 years of age. Neural tube defects (NTDs) are a group of common congenital malformations of the brain and spine generated during neurulation. The genetic basis of this process is still not well known. Whenever an NTD is diagnosed in one of a pair of twins, the other twin should also be evaluated for NTDs.
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Affiliation(s)
- Barbara Spacca
- Department of Neurosurgery-Littlewoods Neuroscience Unit, Royal Liverpool Children's Hospital NHS Trust, Liverpool, United Kingdom
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26
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Chen X, Watkins R, Delot E, Reliene R, Schiestl RH, Burgoyne PS, Arnold AP. Sex difference in neural tube defects in p53-null mice is caused by differences in the complement of X not Y genes. Dev Neurobiol 2008; 68:265-73. [PMID: 18004765 DOI: 10.1002/dneu.20581] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
To shed light on the biological origins of sex differences in neural tube defects (NTDs), we examined Trp53-null C57BL/6 mouse embryos and neonates at 10.5 and 18.5 days post coitus (dpc) and at birth. We confirmed that female embryos show more NTDs than males. We also examined mice in which the testis-determining gene Sry is deleted from the Y chromosome but inserted onto an autosome as a transgene, producing XX and XY gonadal females and XX and XY gonadal males. At birth, Trp53 nullizygous mice were predominantly XY rather than XX, irrespective of gonadal type, showing that the sex difference in the lethal effect of Trp53 nullizygosity by postnatal day 1 is caused by differences in sex chromosome complement. At 10.5 dpc, the incidence of NTDs in Trp53-null progeny of XY* mice, among which the number of the X chromosomes varies independently of the presence or absence of a Y chromosome, was higher in mice with two copies of the X chromosome than in mice with a single copy. The presence of a Y chromosome had no protective effect, suggesting that sex differences in NTDs are caused by sex differences in the number of X chromosomes.
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Affiliation(s)
- Xuqi Chen
- Department of Physiological Science, University of California, Los Angeles, CA, USA
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Abstract
OBJECTIVE Encephalocele is classified as a neural tube defect, but questions have been raised regarding whether its epidemiological characteristics are similar to those of other neural tube defects. DESIGN We compared characteristics of temporal trends in, and the impact of folic acid grain fortification on, the prevalence of encephalocele, spina bifida, and anencephaly using data from the Metropolitan Atlanta Congenital Defects Program, a population-based birth defects surveillance system. Prevalences of encephalocele, spina bifida, and anencephaly were compared by maternal age, gender, race, birth weight, ascertainment period (1968-1981, 1982-1993, or 1994-2002), and fortification period (1994-1996 [prefortification] and 1998-2002 [postfortification]) using prevalence ratios with 95% confidence intervals. Temporal trends were assessed using Poisson and negative binomial regression models. RESULTS Prevalence rates of encephalocele (n = 167), spina bifida (n = 650), and anencephaly (n = 431) were 1.4, 5.5, and 3.7 per 10 000 live births, respectively. Encephalocele was similar to anencephaly in showing an increased prevalence among girls and multiple gestation pregnancies and to spina bifida and anencephaly in an annual prevalence decrease between 1968 and 2002 (-1.2% for encephalocele, -4.2% for spina bifida, and -3.6% for anencephaly). With fortification, prevalence decreased for spina bifida but not significantly for encephalocele or anencephaly. CONCLUSIONS Encephalocele shows more similarities to spina bifida or anencephaly than it shows differences with respect to characteristics, temporal trend, and impact of fortification. Additional studies should be done to explore the etiologic heterogeneity of encephalocele using better markers of folate status and a wider range of risk factors.
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Affiliation(s)
- Courtney A Rowland
- National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, 1600 Clifton Rd, Mailstop E-86, Atlanta, Georgia 30333, USA
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Martínez de Villarreal LE, Arredondo P, Hernández R, Villarreal JZ. Weekly Administration of Folic Acid and Epidemiology of Neural Tube Defects. Matern Child Health J 2006; 10:397-401. [PMID: 16900407 DOI: 10.1007/s10995-006-0082-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2005] [Accepted: 04/13/2006] [Indexed: 12/01/2022]
Abstract
OBJECTIVE In 1999, a folic acid campaign for prevention of neural tube defects was started in Nuevo León, México, with the recommendation of taking a 5000 -mcg tablet of folic acid per week. The purpose of this study was to compare the epidemiology of neural tube defects after four years of the campaign. METHODS Cases of anencephaly, spina bifida, and encephalocele (ICD Q00, Q01, Q05, 10th Ed.) from public and private hospitals were registered by immediate notification, death certificates, and fetal death registries. Comparisons of neural tube defects rates, phenotype distribution of cases, and sex ratios, registered before and after the folic acid campaign, were done using the Student's t Test and Chi square test. RESULTS There was a 50% reduction in the incidence of anencephaly and spina bifida cases from 93 in 1999 (1.04x1000) to 46 in the year 2003 (0.56x1000) (p<0.001). Spina bifida cases declined up to 70% in 2002 and anencephaly cases up to 50% in 2003. In 1999, overall, the ratio (females: males) was 0.66 with female excess; the sex ratio was similar for anencephaly and spina bifida cases. In the year 2000, female cases showed a significant reduction for both spina bifida and anencephaly (75% and 56% respectively); the sex ratio was 0.57 with a greater male excess for both phenotypes. CONCLUSIONS Weekly administration of 5000 mcg of folic acid reduces the incidence of neural tube defects 50%, primarily spina bifida, with a higher reduction of female cases.
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Affiliation(s)
- Laura E Martínez de Villarreal
- Departamento de Genética, Facultad de Medicina, Universidad Autónoma de Nuevo León, and Hospital Regional #23 I.M.S.S. Monterrey, N.L., 64460, México.
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Farley TL. A reproductive history of mothers with spina bifida offspring--a new look at old issues. Cerebrospinal Fluid Res 2006; 3:10. [PMID: 16879755 PMCID: PMC1557536 DOI: 10.1186/1743-8454-3-10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2006] [Accepted: 08/01/2006] [Indexed: 11/12/2022] Open
Abstract
Background Spina bifida is a disorder of the cerebrospinal fluid system associated with failure of neural tube closure in the fetus. Reproductive history studies of mothers with spina bifida offspring have often been conducted shortly after the affected child's birth. In this study, a large group of community-based mothers were studied after most had completed their families. The aims were to present a more comprehensive reproductive history and to test several hypotheses regarding the nature of spina bifida. Methods Data from 271 mothers was collected by interview 18.3 mean years after the affected child's birth. Data analysis was by χ-square, Fisher exact test and t test with a p value less than 0.05 considered significant. Results Females made up 56.5% of affected offspring (probands) and 53.1% of unaffected offspring. The spina bifida and anencephaly recurrence rate was 4.0%. The twinning rate was 8.6/1000 live births. 24.4% of mothers had a history of spontaneous abortion and the rate varied by pregnancy order from 87 to 185/1000 live births. Duration of pregnancies subsequent to probands was shorter for female than male probands. Mean birth weight of probands with high lesions exceeded those with low lesions. A spontaneous abortion preceded female probands more often than males as compared to live births. Affected males with high lesions conceived by white mothers were at greater risk to be spontaneously aborted. Previous inter-gestational interval for mothers with no history of spontaneous abortion was longer for probands than unaffected offspring but not for mothers with a history of spontaneous abortion. Conclusion Overall, and for every major subgroup of these mothers, more affected and unaffected female than male offspring were born. Differences by gender and lesion level among probands and between probands and unaffected offspring were consistent with an etiology of unknown genetic factors, hormonal and/or immune system factors.
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Affiliation(s)
- Thomas L Farley
- Arkansas Spinal Cord Commission, 1501 North University Avenue, Little Rock, Arkansas, 72207-5233, USA.
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Djientcheu VDP, Wonkam A, Njamnshi AK, Ongolo-Zogo P, Rilliet B, Morris MA. Discordant encephalocele in monozygotic twins. Am J Med Genet A 2006; 140:525-6. [PMID: 16470746 DOI: 10.1002/ajmg.a.31065] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Fortin A, Rajguru M, Madelenat P, Mahieu-Caputo D. [Neurological outcome of children from twin pregnancies]. ACTA ACUST UNITED AC 2005; 33:563-9. [PMID: 16137916 DOI: 10.1016/j.gyobfe.2005.07.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2005] [Accepted: 07/18/2005] [Indexed: 11/27/2022]
Abstract
The neurological outcome is an important issue regarding twin pregnancies. In fact, twin pregnancy is clearly associated with an important neurological morbidity, roughly 4 times higher than singleton pregnancy. It is possible to distinguish some high-risk situations, making it possible to calculate more accurately the individual risk. The different aetiologies are analysed: hypotrophy, prematurity, malformations, prenatal occurrence of anoxic and ischemic lesions, and particularly the link with monochorionicity. The neurological outcome is mainly depending on hypotrophy and prematurity. However, the rate of long-term neurological complications is not different between twins and singletons after adjustment for term and birth weight. An increased risk of malformation is associated with twin pregnancies, essentially a high rate of abnormal neural tube closing (RR=2). Monochorionic pregnancies have a specific morbidity, not related to these aetiologies, with characteristic anoxic and ischemic lesions. Cerebral palsy is observed in 10-20% of the monochorionic pregnancies, vs 3.7% of the bichorionic ones. These complications are linked to the constant vascular anastomoses, between the circulations of the two monochorionic twins. When the twin-to-twin transfusion syndrome is severe, a poor neurological outcome is observed in 4 to 18% of the surviving children. However, this rate depends on studies, treatments, and methods of neurological evaluation. The laser destruction of anastomoses could decrease this morbidity. The stillbirth rate, either associated or not with twin to twin transfusion syndrome, is increased by monochorionicity. The death of one of the twins is associated with a 20% higher risk of neurological sequelae for the surviving co-twin.
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Affiliation(s)
- A Fortin
- Service de gynécologie-obstétrique, maternité Aline-de-Crépy, hôpital Bichat-Claude-Bernard, 46, rue Henri-Huchard, 75018 Paris, France
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Ben-Ami I, Vaknin Z, Reish O, Sherman D, Herman A, Maymon R. Is there an increased rate of anencephaly in twins? Prenat Diagn 2005; 25:1007-10. [PMID: 16231303 DOI: 10.1002/pd.1233] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND The Israeli Ministry of Health reported an increased rate of twin pregnancies among all cases locally diagnosed as having open neural tube defects. The current study aimed to evaluate whether the etiology of this phenomenon could be attributed either to the twinning or to the mode of conception. METHODS Women admitted to our hospital between January 1997 and July 2004 for termination of pregnancy because of severe fetal abnormality enrolled into this retrospective case series study. They were further subdivided according to mode of conception (spontaneous, in vitro fertilization (IVF) or intracytoplasmic sperm injection (IVF-ICSI) pregnancies). RESULTS Three-hundred and eighty consecutive pregnancies, of which 340 (89%) were singletons, participated in our study. Anencephaly was diagnosed in 26 cases: 19 singletons and 7 twins. In the entire twin population, they were all dichorionic twins and only one co-twin was affected. Five of the twins were conceived by IVF-ICSI. All the anencephalic IVF-ICSI twins had normal karyotypes. All IVF-ICSI study women had taken folic acid 400 mcg/day 3 months before conception and throughout the first trimester of pregnancy. In order to find out the cause of the high rate of anencephaly found in IVF-ICSI pregnancies (33.3%), either the twinning or the IVF-ICSI process, a logistic regression analysis was used. A significant correlation was found only between anencephaly and twinning (p = 0.001, CI = 1.86-12.63), with a risk ratio of 4.85. CONCLUSIONS Our case series data suggest a comparatively higher rate of anencephaly in IVF-ICSI pregnancy secondary to twinning and not because of the assisted reproductive technology. It is suggested that larger epidemiologic studies are conducted to validate our preliminary results.
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Affiliation(s)
- Ido Ben-Ami
- Department of Obstetrics and Gynecology, Assaf Harofeh Medical Center, Zerifin, Tel-Aviv University, Tel-Aviv, Israel
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Abstract
Since the 1970s, the national twin birth rates have been increasing worldwide. Apart from the increasing childbearing age, the main cause is the use of assisted reproductive technologies (ART). To explore the overall consequences of dual embryo transfer (DET), the literature has been reviewed systematically regarding short- and long-term outcomes of IVF/ICSI twin pregnancies i.e. pregnancy complications, maternal risks, obstetric outcome and long-term morbidity including neurological sequelae, cognitive development and family implications. Another consequence of DET is vanishing twins, which seems to be a possible cause of adverse outcome in IVF singletons. The sparse literature on vanishing twins in IVF pregnancies and the influence on the surviving co-twin were also addressed. Finally, to determine the effects of implementing elective single embryo transfer (eSET), trials concerning eSET versus DET were analysed. In the light of the steadily increasing twin birth rates and the findings in this overview, where IVF/ICSI twins carry adverse outcome, it should be emphasized that the major obstacle in IVF remains the high twin birth rate. Furthermore vanishing twins account for another hazard of DET. These problems can be resolved by implementing eSET, diminishing the twin birth rate without affecting the overall goal of achieving a healthy infant.
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Affiliation(s)
- Anja Pinborg
- The Fertility Clinic, The Juliane Marie Centre, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej, Copenhagen, Denmark.
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Lisi A, Botto LD, Rittler M, Castilla E, Bianca S, Bianchi F, Botting B, De Walle H, Erickson JD, Gatt M, De Vigan C, Irgens L, Johnson W, Lancaster P, Merlob P, Mutchinick OM, Ritvanen A, Robert E, Scarano G, Stoll C, Mastroiacovo P. Sex and congenital malformations: an international perspective. Am J Med Genet A 2005; 134A:49-57. [PMID: 15704121 DOI: 10.1002/ajmg.a.30514] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The study evaluated the sex distribution of major isolated malformations and common trisomies among a large and geographically varied sample. Eighteen registries from 24 countries contributed cases, which were centrally reviewed and classified in three clinical types as isolated, associated, or syndromic. We selected cases of 26 major defects (n = 108,534); trisomy 21, 18, and 13 (n = 30,114); other syndromes (n = 2,898); and multiple congenital anomalies (n = 24,197), for a total of 165,743 cases. We observed a significant deviation of sex distribution (compared to a sex ratio of 1.06 or male proportion of 51.4%) for 24 of the 29 groups (a male excess in 16, a female excess in 8), and in 8 of such groups these estimates varied significantly across registries. A male excess was noted for two left obstructive cardiac defects (hypoplastic left heart and coarctation of the aorta) and a female excess for all the main types of neural tube defects. A male excess was seen for omphalocele but not gastroschisis. For neural tube defects the female excess tended to be stronger in areas with historically high prevalence for these defects. For 15 of the 26 birth defects the sex distribution differed among isolated, associated, and syndromic cases. Some of these epidemiologic commonalities are consistent with known or putative developmental processes. Further, the geographic variation for some defects may reflect local prevalence rates and risk factors. Finally, the findings underscore the need for clinical classification (e.g., into isolated, multiple, syndromes) in studies of birth defects.
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Lundberg YW, Cabrera RM, Greer KA, Zhao J, Garg R, Finnell RH. Mapping a chromosomal locus for valproic acid-induced exencephaly in mice. Mamm Genome 2004; 15:361-9. [PMID: 15170225 DOI: 10.1007/s00335-004-2345-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2003] [Accepted: 01/06/2004] [Indexed: 10/26/2022]
Abstract
Human neural tube defects (NTDs) are among the most common congenital defects. They have a highly heterogeneous etiology, and, in addition to those seen in association with genetic syndromes, there are also NTDs induced by pharmaceutical compounds in utero, such as the widely used anti-epileptic drug valproic acid (VPA). Although familial studies have suggested a genetic contribution to VPA-induced NTDs, this trait has not been adequately studied, nor have the responsible genetic factors been identified. We generated a series of mouse crosses and backcrosses using the highly inbred SWV/Fnn and C57BL/6J strains, in order to identify possible chromosomal loci contributing to VPA sensitivity. When exposed to a high dose of sodium VPA (600 mg/kg) via maternal intraperitoneal injection on gestational day E8.5, the fetuses manifested exencephaly in a strain-dependent manner. Our data show an autosomal recessive trait, plus a gender-related effect or an overall X-Chromosome (Chr) effect, as being primarily responsible for determining sensitivity to VPA-induced exencephaly. Genome scanning and further linkage analysis of 131 exencephalic backcross fetuses identified a major locus linked to D7Mit285 (p < 2 x 10(-6)), exceeding the threshold for significant linkage. These results suggest a major chromosomal locus associated with the sensitivity to VPA-induced exencephaly in mice.
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Affiliation(s)
- Yunxia Wang Lundberg
- Genetics Department, Boys Town National Research Hospital, Omaha, Nebraska 68131, USA.
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Shaw GM, Carmichael SL, Kaidarova Z, Harris JA. Differential risks to males and females for congenital malformations among 2.5 million California births, 1989-1997. ACTA ACUST UNITED AC 2003; 67:953-8. [PMID: 14745913 DOI: 10.1002/bdra.10129] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Although many studies have observed variations in the prevalence of specific malformations by sex, there is a lack of population-based data on potential malformation prevalence differences by sex at birth. METHODS Our objective was to explore differences in the prevalence of structural congenital malformation phenotypes between sexes in a California population of 2.5 million live- and stillbirths, using data from a population-based active surveillance system. Ascertainment was performed among offspring of California women who delivered in nonmilitary hospitals during the period of 1989-1997. Malformations were grouped according to the four-digit malformation codes of the British Pediatric Association. RESULTS Overall, 32,619 males and 21,835 females were considered to have structural congenital malformations, with prevalences of 2.52% and 1.76%, respectively. Thus, males demonstrated a malformation prevalence that was 22% higher than that in females. Using a criterion of a 40% increase or decrease in the relative risk for males, increased risks for 15 and decreased risks for 17 specific malformation categories were observed. Increased risks were associated with most organ systems, with the notable exception of the nervous system (increased risks for nervous system malformations were observed among female births). Risks were not substantially influenced by adjusting for maternal age, race/ethnicity, parity, or education. CONCLUSIONS Our observations extend the relatively few studies that have investigated differential prevalences of a large number of specific structural malformations between male and female births.
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Affiliation(s)
- Gary M Shaw
- March of Dimes Birth Defects Foundation, California Birth Defects Monitoring Program, Berkeley, California 94710, USA.
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Malek FA, Möritz KU, Fanghänel J, Bienengräber V. Sex-related differences in procarbazine-induced cleft palate and microgenia and the anti-teratogenic effect of prenatal folic acid supplementation in rats. Ann Anat 2003; 185:465-70. [PMID: 14575274 DOI: 10.1016/s0940-9602(03)80109-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Sex-related differences in the frequency of cleft palates and microgenia in rat fetuses prenatally treated with procarbazine (200 mg/kg on day 14 of gestation (GD14), group 1), and the anti-teratogenic effect of prenatal folic acid supplementation (4 mg/kg on GD14 through GD17, group 2) were studied in LEW.1A rats. In group 1, complete clefts were observed in 69% of the male and in 36% of the female fetuses while incomplete clefts (present only in the hard palate) were exhibited by 31% of the males and 43% of the females. Microgenia occurred in all males but only in 64% of the female fetuses. In group 2, the prenatal folic acid supplementation significantly reduced the occurrence frequency of complete clefts to 9% in males and to 0% in females. In contrast, incomplete clefts increased to 82% in males and 91% in females. Microgenias were reduced to 73% and 57% in male and female fetuses, respectively. Since incomplete clefts present in the hard palate are assumed to be residues of spontaneous intra-uterine repair processes of exogenously induced complete palatal clefts, we conclude that prenatal supplementation with folic acid at a dose of 4 mg/kg promotes the intra-uterine repair of cleft palates and offers a partial protection against procarbazine teratogenicity. Furthermore, it is deduced that gender-specific differences exist in the susceptibility to procarbazine and in the anti-teratogenic effect of folic acid on procarbazine-induced microgenia.
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Affiliation(s)
- F A Malek
- Department of Anatomy, Ernst Moritz Arndt University, Friedrich-Loeffler-Strasse 23 c, D-17487 Greifswald, Germany
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Davies BR, Durán M. Malformations of the cranium, vertebral column, and related central nervous system: Morphologic heterogeneity may indicate biological diversity. ACTA ACUST UNITED AC 2003; 67:563-71. [PMID: 14632305 DOI: 10.1002/bdra.10080] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND We conducted an autopsy study of neural tube defects (NTDs) to determine whether there is a relation between the localization of the lesion and the sex of the fetus or infant, and the presence of other malformations. METHODS Included were 97 autopsies of infants/fetuses with anencephaly or spina bifida at any level and weighing more than 500 gm. The topographical divisions studied were: 1) isolated cranial lesions, 2) superior spina bifida with or without occipital lesion, and 3) isolated lower spina bifida. RESULTS In group 1 (46 cases) there were lesions of the vertebral column, mainly cervical, and other anomalies of the "schisis" type. Group 2 (24 cases) showed more extensive involvement of the vertebral column and more cases with multiple anomalies (p = 0.001) of a varied spectrum, not only the schisis type; in group 3 (27 cases) the cases involved a few other malformations. In group 2 there was no sex preference (females 46%), but the other, more localized lesions (groups 1 and 3) were found predominantly in females (71%). CONCLUSIONS Localized lesions, whether involving the cranium or lumbar spine, are formed by a mechanism that favors the female gender, whereas upper spina bifida, which is usually accompanied by cranial involvement, results from another mechanism (possibly vascular disruption) and is frequently accompanied by other malformations.
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Affiliation(s)
- Belinda R Davies
- Department of Pathology, General Hospital of Mexico, Mexico City, Mexico
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Abstract
Neural tube defects (NTDs)-malformations secondary to abnormal neural tube closure between the third and fourth weeks of gestational age-have a complex and imperfectly understood etiology in which both genetic and environmental factors appear to be involved. A number of specific chromosomal or single-gene disorders, presumably not affected by environmental influences, are associated with the development of NTDs, but such syndromal cases account for a small proportion of NTDs in live-born infants. Analysis of recurrence patterns within families and of twin-concordance data provides evidence of a genetic influence in nonsyndromal cases, but factors such as socioeconomic status and geographic area (independent of race or ethnicity) are also associated with variations in the incidence of NTDs. The prevalence at birth of both anencephaly and spina bifida has decreased, but the advent of antenatal diagnosis and elective termination of affected pregnancies has undermined the reliability of birth prevalence rate as an estimate of incidence. Some occupational and other exposures, including maternal use of antiepileptic drugs (AEDs), are associated with increased risk for NTDs. Among women who have had an NTD-affected pregnancy, recurrence risk is markedly higher than the risk for a first NTD-affected pregnancy in the general population. There is strong evidence, overall, for a protective effect of adequate folate consumption. In some high-risk groups, however, such as women taking AEDs, folate supplementation has not been proven to reduce NTD risk.
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Affiliation(s)
- Lauren Frey
- Department of Neurology, G. H. Sergievsky Center, College of Physicians & Surgeons, Columbia University, New York, New York 10032, USA
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Lary JM, Paulozzi LJ. Sex differences in the prevalence of human birth defects: a population-based study. TERATOLOGY 2001; 64:237-51. [PMID: 11745830 DOI: 10.1002/tera.1070] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Sex differences in the prevalence of several human birth defects have often been reported in the literature, but the extent of sex differences for most birth defects is unknown. To determine the full extent of sex differences in birth defects in a population, we examined population-based data from the Metropolitan Atlanta Congenital Defects Program (MACDP). METHODS MACDP records were analyzed for 1968 through 1995. We determined the sex-specific prevalence of all major birth defects, using the total number of live births by sex during these years as the denominator. For each specific defect, we calculated a relative risk with regard to sex on the basis of the ratio of prevalence among males to prevalence among females. Male-female relative risks were also determined for total major birth defects and for several broad categories of defects. RESULTS The overall prevalence of major defects at birth was 3.9% among males and 2.8% among females. All but two of the major categories of birth defects (nervous system defects and endocrine system defects) had a higher prevalence among males. Defects of the sex organs were eight and one-half times more prevalent among males and accounted for about half of the increased risk of birth defects among males relative to females. Urinary tract defects were 62% more prevalent among males, and gastrointestinal tract defects were 55% more prevalent among males. Among specific defect types, twofold or greater differences in prevalence by sex were common. CONCLUSIONS Our data indicate that sex differences in the prevalence of specific human birth defects are common, and male infants are at greater risk for birth defects than female infants. Several mechanisms have been proposed to account for these differences.
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Affiliation(s)
- J M Lary
- Birth Defects and Pediatric Genetics Branch, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia 30341-3724, USA.
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Ericson A, Källén B. Congenital malformations in infants born after IVF: a population-based study. Hum Reprod 2001; 16:504-9. [PMID: 11228220 DOI: 10.1093/humrep/16.3.504] [Citation(s) in RCA: 266] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The presence of congenital malformations in infants born after IVF was studied from a register consisting of practically all infants born in Sweden after IVF, 1982--1997 (n = 9111). A further 64 infants were studied using only medical records. It is a nation-wide study and has a population-based control group (n = 1,690,577) and relevant potential confounders have been taken into account. There was an excess of congenital malformations registered in the Medical Birth Registry (n = 516, odds ratio = 1.47) but this excess disappeared when confounders were taken into consideration: year of birth, maternal age, parity, and period of unwanted childlessness (odds ratio = 0.89). For some specific conditions, an approximately 3-fold excess risk was seen: neural tube defects, alimentary atresia, omphalocele, and hypospadias (after intracytoplasmatic sperm injection). No excess risk for hypospadias was seen after standard IVF. Various explanations for these findings are discussed. It is postulated that the excess risk for alimentary atresia, like the excess risk for monozygotic twinning after IVF, is a direct consequence of the IVF procedure. The excess risk for hypospadias after ICSI may be related to paternal subfertility with a genetic background. The absolute risk for a congenital malformation in association with IVF is small.
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Affiliation(s)
- A Ericson
- Epidemiological Center, National Board of Health, SE-106 30 Stockholm, Sweden
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Abstract
BACKGROUND Infants with birth defects are more likely to be born small for gestational age (SGA) than are other infants. This study describes a relation noted between the percentage SGA and the percentage male among children with various defect types. The data source was case records collected by the Metropolitan Atlanta Congenital Defects Program, a population-based, active surveillance system, during 1968 through 1998. METHODS The study calculated the correlation between the percentage male and the percentage SGA for isolated cases of 44 different defect types for male-dominant and female-dominant defects separately. RESULTS The correlation coefficient was -0.47 (P < 0.01) for male-dominant defects and 0.20 (P > 0.05) for female-dominant defects. Male-dominant defects were more likely to show less than 15% SGA and more likely to show the strongest risk differences by sex. CONCLUSIONS These results are consistent with genetic causation of strongly skewed sex ratios, at least among male-dominant defects. Review of the literature suggests that defects with sex ratios closer to 1 are likely to have lower recurrence risks and therefore are less likely to be inherited than are other defects with skewed sex ratios. Sex ratios closer to 1 and a high percentage SGA may be markers of acquired or environmental birth defects.
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Affiliation(s)
- L J Paulozzi
- National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia 30341, USA.
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Owen TJ, Halliday JL, Stone CA. Neural tube defects in Victoria, Australia: potential contributing factors and public health implications. Aust N Z J Public Health 2000; 24:584-9. [PMID: 11215005 DOI: 10.1111/j.1467-842x.2000.tb00521.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVES To measure population prevalence and determine potential predictors of neural tube defects. METHOD Analysis of all births reported to a mandated collection of perinatal data, and terminations prior to 20 weeks' gestation that have been reported to a data collection of birth defects in Victoria from 1983 to 1997. Prevalence at birth and risk ratios of infant and maternal characteristics associated with neural tube defects were calculated. RESULTS Prevalence of spina bifida has remained steady for 15 years and was 8.8/10,000 in 1997. Anencephaly increased to 7.9/10,000 in 1997. After exclusion of pregnancy terminations, the 1997 birth prevalence was 4.5/10,000 for spina bifida and 2.4/10,000 for anencephaly. Neural tube defects are identified in 1 in 1600 fetuses, the risk being significantly higher for epileptic women (Adjusted Odds Ratio (AOR) = 3.70, 95% CI 2.25-6.07), multiple births (AOR = 4.56, 95% CI 3.46-6.02), teenage mothers (AOR = 1.47, 95% CI 1.09-2.00) compared with those aged 25-29, and women with three or more previous pregnancies (AOR = 1.40, 95% CI 1.10-1.78). The risk was lower for women of East Asian (AOR = 0.70, 95% CI 0.49-1.00) and Middle Eastern origin (AOR = 0.60, 95% CI 0.35-1.02) and these differences were approaching statistical significance. CONCLUSION Total prevalence of neural tube defects did not decline up to 1997. IMPLICATIONS It is unlikely that targeting 'at risk' groups identified in this study would make a difference to neural tube defect incidence. However, consideration could be given to identifying larger 'at risk' groups such as those with homocysteine metabolism defects.
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Affiliation(s)
- T J Owen
- Perinatal Data Collection Unit, Department of Human Services, PO Box 4003, Melbourne, Victoria 3053
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Holmberg J, Clarke DL, Frisén J. Regulation of repulsion versus adhesion by different splice forms of an Eph receptor. Nature 2000; 408:203-6. [PMID: 11089974 DOI: 10.1038/35041577] [Citation(s) in RCA: 283] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Eph tyrosine kinase receptors and their membrane-bound ephrin ligands mediate cell interactions and participate in several developmental processes. Ligand binding to an Eph receptor results in tyrosine phosphorylation of the kinase domain, and repulsion of axonal growth cones and migrating cells. Here we report that a subpopulation of ephrin-A5 null mice display neural tube defects resembling anencephaly in man. This is caused by the failure of the neural folds to fuse in the dorsal midline, suggesting that ephrin-A5, in addition to its involvement in cell repulsion, can participate in cell adhesion. During neurulation, ephrin-A5 is co-expressed with its cognate receptor EphA7 in cells at the edges of the dorsal neural folds. Three different EphA7 splice variants, a full-length form and two truncated versions lacking kinase domains, are expressed in the neural folds. Co-expression of an endogenously expressed truncated form of EphA7 suppresses tyrosine phosphorylation of the full-length EphA7 receptor and shifts the cellular response from repulsion to adhesion in vitro. We conclude that alternative usage of different splice forms of a tyrosine kinase receptor can mediate cellular adhesion or repulsion during embryonic development.
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Affiliation(s)
- J Holmberg
- Department of Cell and Molecular Biology, Karolinska Institute, Stockholm, Sweden.
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Mastroiacovo P, Castilla EE, Arpino C, Botting B, Cocchi G, Goujard J, Marinacci C, Merlob P, Métneki J, Mutchinick O, Ritvanen A, Rosano A. Congenital malformations in twins: an international study. AMERICAN JOURNAL OF MEDICAL GENETICS 1999; 83:117-24. [PMID: 10190482 DOI: 10.1002/(sici)1096-8628(19990312)83:2<117::aid-ajmg7>3.0.co;2-4] [Citation(s) in RCA: 142] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Data provided by nine registries based in European and Latin America countries were analyzed to assess whether there is an excess of malformations in twins compared to singletons. Specific congenital malformations were coded according to the ninth revision of the International Classification of Diseases (ICD). Malformation rates and rate ratios (RR) for twins compared to singletons were calculated for each registry, and the homogeneity of the RRs was tested using the test of Breslow and Day. If departure from homogeneity in the different registries was not significant, registry-adjusted RRs with 95% confidence intervals were calculated. Overall, among 260,865 twins, 5,572 malformations were reported. A total of 101 different types of malformations or groups of defects was identified, and a homogeneous estimate of the RRs among registries was found for 91.1% of the malformations. Thirty-nine of the 92 malformations with homogeneous estimates of RRs were more common in twins than in singletons. For the remaining nine malformations, heterogeneous estimates of RRs were obtained. This study confirms the majority of already known associations and further identifies previously unreported malformations associated with twins. In conclusion, there is an excess of malformations in twins compared with singletons, and all anatomical sites are involved. The number of specific malformations associated with twins is higher than that previously reported in smaller studies.
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Affiliation(s)
- P Mastroiacovo
- Birth Defects Unit, Catholic University, International Centre for Birth Defects, Rome, Italy.
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Rotmensch S, Celentano C, Shalev J, Vishne TH, Lipitz S, Ben-Rafael Z, Glezerman M. Midtrimester maternal serum screening after multifetal pregnancy reduction in pregnancies conceived by in vitro fertilization. J Assist Reprod Genet 1999; 16:8-12. [PMID: 9987687 PMCID: PMC3468214 DOI: 10.1023/a:1022585326896] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE Data about the effect of multifetal pregnancy reduction on midtrimester maternal serum levels of alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and unconjugated estriol (uE3) are scarce and contradictory. Differing gestational ages at fetal reduction, transvaginal versus transabdominal needle insertion, and injection of different feticidal agents compound the analysis of published data. METHODS We examined clinical and laboratory data about 27 high-order gestations that were reduced to twins in the first trimester. Fetal reductions were performed transabdominally at 11.41 +/- 1.15 weeks' gestation by fetal intrathoracic injection of KCl, and maternal blood sampling was performed at 16.48 +/- 1.05 weeks. "Pseudo-risks" for singleton pregnancies were calculated by correcting serum analyte levels for twins. RESULTS Twenty-four (88.9%) of 27 patients had maternal serum AFP levels above 2.0 MoM (mean, 4.60 +/- 3.48 MoM; range, 1.49-14.85 MoM), however, none of the newborns had structural anomalies. AFP serum levels did not correlate with the number of reduced fetuses or with adverse obstetric outcome. The mean hCG levels were 1.22 +/- 0.49 MoM (range, 0.14-2.47), and the mean uE3 levels were 1.15 +/- 0.31 MoM (range, 0.56-1.84). Based on maternal age alone, seven patients (25.9%) would have been offered amniocentesis for a term Down syndrome risk greater than 1:384, whereas combined risk calculations with hCG and uE3 levels resulted in 1 (3.7%) screen-positive case (P < 0.01).
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Affiliation(s)
- S Rotmensch
- Department of Obstetrics and Gynecology, Edith Wolfson Medical Center, Holon, Israel
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Abstract
The paper describes associated malformations in infants born with neural tube defects (N = 3,809) from three large malformation registers and in fetuses aborted because of a diagnosed neural tube defect (N = 748) from two of the registers. In infants, upper spina bifida and encephalocele are more often associated with non-neural malformations than anencephaly or lower spina bifida. Aborted fetuses with spina bifida or encephalocele have associated malformations registered more often than infants with those neural tube defects, but the opposite is true for anencephaly. The degree of detail of the investigation of an aborted specimen or a perinatally dead infant will contribute to such differences but they can also depend on the fact that prenatal detection may be facilitated by the simultaneous presence of other malformations like body wall defects. Also, fetuses with many malformations may be more prone to abort spontaneously late in pregnancy. Variable prenatal diagnosis may, therefore, explain population differences in the pattern of associated malformations. The type of associated malformation differs with the level of the neural tube defect: this could be due to different causal mechanisms or be a question of cranio-caudal level and/or timing. For limb reduction defects, however, we did not find any association between upper limb and upper neural tube defects or lower limb and lower neural tube defects. These findings together with other epidemiological data support the idea that upper and lower neural tube defects may have different significance in epidemiological studies and should be treated separately.
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Affiliation(s)
- B Kälién
- Tornblad Institute, University of Lund, Sweden.
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Abstract
Splitting birth defects into dysmorphologically homogeneous groups might improve the ability to detect a genetic risk factor or teratogenic exposure. With regard to spina bifida, recent studies suggest that etiologic heterogeneity exists within the group of spina bifida, although exogenous risk factors have been sparsely evaluated for subgroups. In the present study, 210 spina bifida patients were classified into relatively homogeneous groups, based on retrospective information on appearance and functional aspects of the lesion abstracted from medical records of the patients. We compared high with low spina bifida, and open with closed spina bifida, and investigated whether risk factors for spina bifida such as maternal age, antiepileptic drug use, parental occupation, and genetic factors were specifically associated with these homogeneous subclasses. For these comparisons, a referent group of 671 children was used. Although classifying spina bifida into homogeneous subclasses presented some difficulties and numbers were small, this study provides some evidence for different risk profiles for subclasses of spina bifida. The sex ratio, the proportion of miscarriages of siblings, and maternal age did not differ among the different subclasses of spina bifida. However, children with a positive family history of neural tube defects (NTDs) had a higher risk of high spina bifida [odds ratio (OR) = 6.3, 95% confidence interval (CI): 1.7-19.2] than of low spina bifida (OR = 2.1, 95% CI: 1.0-4.2). Siblings with NTDs were more common in cases with high spina bifida and cases with open spina bifida. A strongly increased risk of high spina bifida was found for male welders (OR = 12.1, 95% CI: 1.5-64.2), whereas the risk of low spina bifida was much lower (OR = 1.6, 95% CI: 0.2-7.9). For mothers with agricultural occupations, a strongly increased risk was observed for open spina bifida (OR = 14.3, 95% CI: 2.9-77.7), whereas none of 107 cases with closed spina bifida had a mother with an occupation in agriculture. Due to small numbers, the results must be interpreted with caution.
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Affiliation(s)
- B M Blatter
- Department of Medical Informatics, Epidemiology, and Statistics, University of Nijmegen, The Netherlands
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