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Boer LL, Winter E, Gorissen B, Oostra RJ. Phenotypically Discordant Anomalies in Conjoined Twins: Quirks of Nature Governed by Molecular Pathways? Diagnostics (Basel) 2023; 13:3427. [PMID: 37998563 PMCID: PMC10669976 DOI: 10.3390/diagnostics13223427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 10/24/2023] [Accepted: 11/07/2023] [Indexed: 11/25/2023] Open
Abstract
A multitude of additional anomalies can be observed in virtually all types of symmetrical conjoined twins. These concomitant defects can be divided into different dysmorphological patterns. Some of these patterns reveal their etiological origin through their topographical location. The so-called shared anomalies are traceable to embryological adjustments and directly linked to the conjoined-twinning mechanism itself, inherently located within the boundaries of the coalescence area. In contrast, discordant patterns are anomalies present in only one of the twin members, intrinsically distant from the area of union. These dysmorphological entities are much more difficult to place in a developmental perspective, as it is presumed that conjoined twins share identical intra-uterine environments and intra-embryonic molecular and genetic footprints. However, their existence testifies that certain developmental fields and their respective developmental pathways take different routes in members of conjoined twins. This observation remains a poorly understood phenomenon. This article describes 69 cases of external discordant patterns within different types of otherwise symmetrical mono-umbilical conjoined twins and places them in a developmental perspective and a molecular framework. Gaining insights into the phenotypes and underlying (biochemical) mechanisms could potentially pave the way and generate novel etiological visions in the formation of conjoined twins itself.
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Affiliation(s)
- Lucas L. Boer
- Department of Medical Imaging, Section Anatomy and Museum for Anatomy and Pathology, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
| | - Eduard Winter
- Pathologisch-Anatomische Sammlung im Narrenturm-NHM, 1090 Vienna, Austria
| | - Ben Gorissen
- Department of Medical Imaging, Section Anatomy and Museum for Anatomy and Pathology, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
| | - Roelof-Jan Oostra
- Department of Medical Biology, Sections Clinical Anatomy & Embryology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
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Dirican EK, Olgan S. On the origin of zygosity and chorionicity in twinning: evidence from human in vitro fertilization. J Assist Reprod Genet 2021; 38:2809-2816. [PMID: 34398401 PMCID: PMC8608953 DOI: 10.1007/s10815-021-02294-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 08/03/2021] [Indexed: 11/24/2022] Open
Abstract
Assisted reproduction is presumed to increase monozygotic twin rates, with the possible contribution of laboratory and medical interventions. Monozygotic dichorionic gestations are supposed to originate from the splitting of an embryo during the first four days of development, before blastocyst formation. Single embryo transfers could result in dichorionic pregnancies, currently explained by embryo splitting as described in the worldwide used medical textbooks, or concomitant conception. However, such splitting has never been observed in human in vitro fertilization, and downregulated frozen cycles could also produce multiple gestations. Several models of the possible origins of dichorionicity have been suggested. However, some possible underlying mechanisms observed from assisted reproduction seem to have been overlooked. In this review, we aimed to document the current knowledge, criticize the accepted dogma, and propose new insights into the origin of zygosity and chorionicity.
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Affiliation(s)
- Enver Kerem Dirican
- Faculty of Medicine, Department of Obstetrics and Gynecology, Center for Reproductive Endocrinology and Assisted Reproduction, Akdeniz University, Antalya, 07100 Turkey
| | - Safak Olgan
- Faculty of Medicine, Department of Obstetrics and Gynecology, Center for Reproductive Endocrinology and Assisted Reproduction, Akdeniz University, Antalya, 07100 Turkey
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Natural human chimeras: A review. Eur J Med Genet 2020; 63:103971. [PMID: 32565253 DOI: 10.1016/j.ejmg.2020.103971] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 05/06/2020] [Accepted: 06/01/2020] [Indexed: 12/24/2022]
Abstract
The term chimera has been borrowed from Greek mythology and has a long history of use in biology and genetics. A chimera is an organism whose cells are derived from two or more zygotes. Recipients of tissue and organ transplants are artificial chimeras. This review concerns natural human chimeras. The first human chimera was reported in 1953. Natural chimeras can arise in various ways. Fetal and maternal cells can cross the placental barrier so that both mother and child may become microchimeras. Two zygotes can fuse together during an early embryonic stage to form a fusion chimera. Most chimeras remain undetected, especially if both zygotes are of the same genetic sex. Many are discovered accidently, for example, during a routine blood group test. Even sex-discordant chimeras can have a normal male or female phenotype. Only 28 of the 50 individuals with a 46,XX/46,XY karyotype were either true hermaphrodites or had ambiguous genitalia. Blood chimeras are formed by blood transfusion between dizygotic twins via the shared placenta and are more common than was once assumed. In marmoset monkey twins the exchange via the placenta is not limited to blood but can involve other tissues, including germ cells. To date there are no examples in humans of twin chimeras involving germ cells. If human chimeras are more common than hitherto thought there could be many medical, social, forensic, and legal implications. More multidisciplinary research is required for a better understanding of this fascinating subject.
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Ponnudurai R, Shajahan I, Rani A, Jayakar J. Mirror finger patterns of apparent monozygotic twins and sib pairs with Schizophrenia. Indian J Psychiatry 2019; 61:520-525. [PMID: 31579182 PMCID: PMC6767825 DOI: 10.4103/psychiatry.indianjpsychiatry_476_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND Although mirror images are noted in some twins, no such reports are available for twins and subjects with schizophrenia. AIM The study was to assess the occurrence of mirror image finger patterns in apparent monozygotic twins with schizophrenia. Another objective was to elucidate these characteristics among sib pairs with schizophrenia for comparison with those of the twins. MATERIALS AND METHODS Eight apparent monozygotic twin pairs and eight sib pairs with schizophrenia were investigated. The frequency of identical patterns in the right side finger of one twin and the corresponding left side finger of the other twin was assessed, and similarly on other sides. Similar assessment was made in sib pairs with schizophrenia and normal sib pairs. RESULTS The left middle finger pattern of one of the twin pair was found to be the mirror image of the right middle finger of the other twin in all the twin pairs studied and so was in seven of the sib pairs with schizophrenia. These mirror images of sib pairs with schizophrenia was more than those of normal sib pairs. This difference was accentuated with significantly more of these patterns in the twins in comparison to those among normal sib pairs. Notably, no difference emerged between the sib pairs with schizophrenia and the twins in any of their finger pairs. CONCLUSION Mirror images that are probably due to factors like abnormal genotypes and L- DNA, appear to be promising tools to study the etiology of schizophrenia.
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Affiliation(s)
- R Ponnudurai
- Professor Emeritus, Department of Psychiatry, A.C.S. Medical College and Hospital, Chennai, Tamil Nadu, India.,Formerly Director, Institute of Mental Health, Chennai, Tamil Nadu, India.,Formerly Professor, Department of Psychiatry, Madras Medical College and Government General Hospital, Sri Ramachandra Medical College and Research Institute, Chennai, Tamil Nadu, India
| | - I Shajahan
- Consultant Psychiatrist, Wigan North Recovery Team, Clare House, Phoenix Way, Ince, Wigan WN3 4NW, UK.,Formerly Professor, Institute of Mental Health, Madras Medical College, Chennai, Tamil Nadu, India
| | - A Rani
- Department of Psychiatry, Government Medical College, Ernakulam, Kerala, India
| | - J Jayakar
- Formerly Professor, Institute of Mental Health, Madras Medical College, Chennai, Tamil Nadu, India
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Boer LL, Schepens-Franke AN, Oostra RJ. Two is a Crowd: Two is a Crowd: On the Enigmatic Etiopathogenesis of Conjoined Twinning. Clin Anat 2019; 32:722-741. [PMID: 31001856 PMCID: PMC6849862 DOI: 10.1002/ca.23387] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 04/16/2019] [Indexed: 12/31/2022]
Abstract
In this article, we provide a comprehensive overview of multiple facets in the puzzling genesis of symmetrical conjoined twins. The etiopathogenesis of conjoined twins remains matter for ongoing debate and is currently cited-in virtually every paper on conjoined twins-as partial fission or secondary fusion. Both theories could potentially be extrapolated from embryological adjustments exclusively seen in conjoined twins. Adoption of these, seemingly factual, theoretical proposals has (unconsciously) resulted in crystallized patterns of verbal and graphic representations concerning the enigmatic genesis of conjoined twins. Critical evaluation on their plausibility and solidity remains however largely absent. As it appears, both the fission and fusion theories cannot be applied to the full range of conjunction possibilities and thus remain matter for persistent inconclusiveness. We propose that initial duplication of axially located morphogenetic potent primordia could be the initiating factor in the genesis of ventrally, laterally, and caudally conjoined twins. The mutual position of two primordia results in neo-axial orientation and/or interaction aplasia. Both these embryological adjustments result in conjunction patterns that may seemingly appear as being caused by fission or fusion. However, as we will substantiate, neither fission nor fusion are the cause of most conjoined twinning types; rather what is interpreted as fission or fusion is actually the result of the twinning process itself. Furthermore, we will discuss the currently held views on the origin of conjoined twins and its commonly assumed etiological correlation with monozygotic twinning. Finally, considerations are presented which indicate that the dorsal conjunction group is etiologically and pathogenetically different from other symmetric conjoined twins. This leads us to propose that dorsally united twins could actually be caused by secondary fusion of two initially separate monozygotic twins. An additional reason for the ongoing etiopathogenetic debate on the genesis of conjoined twins is because different types of conjoined twins are classically placed in one overarching receptacle, which has hindered the quest for answers. Clin. Anat. 32:722-741, 2019. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Lucas L Boer
- Department of Anatomy and Museum for Anatomy and Pathology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Annelieke N Schepens-Franke
- Department of Anatomy and Museum for Anatomy and Pathology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Roelof Jan Oostra
- Department of Medical Biology, Section Clinical Anatomy & Embryology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Calero Ruiz MM, Mangano Armada AI, Gutiérrez Romero JM, Torrejón Cardoso R. Quadruple pregnancy after post-IVF/ICSI transfer of blastocysts. Rev Int Androl 2019; 18:39-42. [PMID: 30880130 DOI: 10.1016/j.androl.2018.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Accepted: 11/18/2018] [Indexed: 10/27/2022]
Abstract
Clinical case of a quadruple pregnancy (monochorionic diamniotic and dichorionic diamniotic) after the transfer of two blastocysts generated by intracytoplasmic sperm injection (ICSI). This is the case of a 29-year-old woman patient with transfer of two blastocysts after long cultivation of 6 embryos generated by ICSI and vitrified on day +3. This revealed quadruple clinical pregnancy (monochorionic diamniotic and dichorionic diamniotic) of 56 days of evolution by transvaginal ultrasound. The couple decided to undergo a selective embryonic reduction of the monochorionic diamniotic pregnancy after receiving information about the risks arising from it. After that embryonic reduction the uncomplicated pregnancy continued until 36 weeks of gestation, achieving reproductive success with the birth of two babies alive and healthy.
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Affiliation(s)
| | - Ana Isabel Mangano Armada
- UGC Intercentros Hospitales Universitarios Puerta del Mar/Puerto Real Atención Integral a la Mujer, Cádiz, Spain
| | | | - Rafael Torrejón Cardoso
- UGC Intercentros Hospitales Universitarios Puerta del Mar/Puerto Real Atención Integral a la Mujer, Cádiz, Spain
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7
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Wenk RE. A review of the biology and classification of human chimeras. Transfusion 2018; 58:2054-2067. [DOI: 10.1111/trf.14791] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 04/25/2018] [Accepted: 05/10/2018] [Indexed: 12/15/2022]
Affiliation(s)
- Robert E. Wenk
- Relationship Testing Accreditation Program Unit; Baltimore Maryland
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8
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Hershenov R, Doroski D. Twin Inc. THEORETICAL MEDICINE AND BIOETHICS 2018; 39:301-319. [PMID: 30167942 DOI: 10.1007/s11017-018-9461-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
This paper presents an account of how human spontaneous embryonic chimeras are formed. On the prevalent view in the philosophical literature, it is said that chimeras are the product of two embryos that fuse to form a new third embryo. We call this version of fusion synthesis. In contrast to synthesis, we present an alternative mechanism for chimera formation called incorporation, wherein one embryo incorporates the cells of a second embryo into its body. We argue that the incorporation thesis explains other types of chimera formation, which are better understood, and is more consistent than synthesis with what is known about embryological development. Incorporation also has different implications than synthesis and so avoids the philosophical puzzles that are often said to accompany embryonic chimera formation-puzzles which pose problems to the human embryo's persistence from fertilization to the fetal stage of human development.
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Affiliation(s)
- Rose Hershenov
- Department of Philosophy, Niagara University, Lewiston, NY, USA.
- Romanell Center for Clinical Ethics and the Philosophy of Medicine, University at Buffalo, Buffalo, NY, USA.
| | - Derek Doroski
- Department of Biology, Franciscan University at Steubenville, Steubenville, OH, USA
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Tracing the structural origins of atypical language representation: consequences of prenatal mirror-imaged brain asymmetries in a dizygotic twin couple. Brain Struct Funct 2018; 223:3757-3767. [PMID: 30062562 DOI: 10.1007/s00429-018-1717-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Accepted: 07/13/2018] [Indexed: 01/16/2023]
Abstract
We investigated the predictive value of prenatal superior temporal sulcus (STS) depth asymmetry in a special case of a female dizygotic twin that showed inverted prenatal asymmetry of this structure. For this purpose, we performed a follow-up investigation in this former fetus at the age of seven, where we assessed the functional language lateralization using task-based and resting-state functional magnetic resonance imaging (fMRI). As control group we employed her twin brother, who showed a typical folding pattern prenatally, as well as a complementary set of four age-matched children that had fetal MRI of their brains and typical STS depth asymmetry. We could show that the twin with the atypical fetal asymmetry of the STS also showed significantly differing rightward language lateralization in the frontal and temporal lobes. Additionally, resting-state data suggest a stronger connectivity between inferior frontal gyri in this case. The twin showed normal cognitive development. This result gives a first glimpse into the STS' atypical asymmetry being a very early morphological marker for later language lateralization.
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10
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Fertilization and Early Embryonic Errors. CHIMERISM 2018. [DOI: 10.1007/978-3-319-89866-7_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Ariel I, Goldman-Wohl D, Yagel S, Gazit E, Loewenthal R. Triple paternal contribution to a normal/complete molar chimeric singleton placenta. Hum Reprod 2017; 32:993-998. [PMID: 28333325 DOI: 10.1093/humrep/dex053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Accepted: 02/28/2017] [Indexed: 11/13/2022] Open
Abstract
A comprehensive study of unusual cases of placental pathology may provide insight into mechanisms of normal human fertilization and early embryonic development by examining the exception to the rule. A gravida three para two 39-year-old woman was monitored by ultrasound from 16 weeks of gestation for cystic placenta. A female newborn was born at 36 weeks gestation. Pathologic examination of the partially cystic placenta revealed a singleton placenta comprised of 2/3 normal placenta and 1/3 complete hydatidiform mole, largely degenerated. Immunostaining for p57 was negative in stromal cells of the molar villi. Chromogenic in-situ hybridization revealed diploidy in both normal and molar parts. A total of 16 microsatellites were studied by short tandem repeat analysis, 11 of which were informative. The analysis revealed bipaternal molar tissue of dispermic origin. The paternal monospermic contribution to the normal part was different from that in the molar part, thus resulting in tripaternal contribution to the conceptus. A chimera is a single organism composed of two or more different populations of genetically distinct cells that originated from different zygotes (tetragametic) whereas mosaic is a mixture of two cell lines in one organism originating from one zygote. The possible mechanisms leading to the formation of chimeric/mosaic placenta in our case (one of the components being complete hydatidiform mole), including twinning, fusion at an early embryonic stage and diploidization of triploids, are discussed.
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Affiliation(s)
- I Ariel
- The Perinatal Pathology Unit, Department of Pathology, Hadassah-Hebrew University Medical Center, Mount Scopus, PO Box 24035, Jerusalem il-91240, Israel
| | - D Goldman-Wohl
- The Magda and Richard Hoffman Center for Human Placenta Research, Department of Obstetrics and Gynecology, Hadassah-Hebrew University Medical Center, Mount Scopus, Jerusalem, Israel
| | - S Yagel
- The Magda and Richard Hoffman Center for Human Placenta Research, Department of Obstetrics and Gynecology, Hadassah-Hebrew University Medical Center, Mount Scopus, Jerusalem, Israel
| | - E Gazit
- The Laboratory for Tissue typing, Chaim Sheba Medical Center, Tel Hashomer, Israel
| | - R Loewenthal
- The Laboratory for Tissue typing, Chaim Sheba Medical Center, Tel Hashomer, Israel
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Rosenbusch B. Early Fertilization Abnormalities in the Human: An Exhausted Area of Research? J Reprod Infertil 2017; 18:393-396. [PMID: 29201671 PMCID: PMC5691257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Affiliation(s)
- Bernd Rosenbusch
- Corresponding Author: Bernd Rosenbusch, Department of Gynaecology and Obstetrics, University of Ulm, Prittwitzstrasse 43, 89075 Ulm, Germany E-mail:
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Kramer P, Bressan P. Humans as Superorganisms: How Microbes, Viruses, Imprinted Genes, and Other Selfish Entities Shape Our Behavior. PERSPECTIVES ON PSYCHOLOGICAL SCIENCE 2016; 10:464-81. [PMID: 26177948 DOI: 10.1177/1745691615583131] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Psychologists and psychiatrists tend to be little aware that (a) microbes in our brains and guts are capable of altering our behavior; (b) viral DNA that was incorporated into our DNA millions of years ago is implicated in mental disorders; (c) many of us carry the cells of another human in our brains; and (d) under the regulation of viruslike elements, the paternally inherited and maternally inherited copies of some genes compete for domination in the offspring, on whom they have opposite physical and behavioral effects. This article provides a broad overview, aimed at a wide readership, of the consequences of our coexistence with these selfish entities. The overarching message is that we are not unitary individuals but superorganisms, built out of both human and nonhuman elements; it is their interaction that determines who we are.
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Affiliation(s)
- Peter Kramer
- Department of General Psychology, University of Padua, Italy
| | - Paola Bressan
- Department of General Psychology, University of Padua, Italy
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Matias A, Silva S, Martins Y, Blickstein I. Monozygotic twins: Ten reasons to be different. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.diapre.2013.09.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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The potential significance of binovular follicles and binucleate giant oocytes for the development of genetic abnormalities. J Genet 2012; 91:397-404. [DOI: 10.1007/s12041-012-0195-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
AbstractThe science of genetics is undergoing a paradigm shift. Recent discoveries, including the activity of retrotransposons, the extent of copy number variations, somatic and chromosomal mosaicism, and the nature of the epigenome as a regulator of DNA expressivity, are challenging a series of dogmas concerning the nature of the genome and the relationship between genotype and phenotype. According to three widely held dogmas, DNA is the unchanging template of heredity, is identical in all the cells and tissues of the body, and is the sole agent of inheritance. Rather than being an unchanging template, DNA appears subject to a good deal of environmentally induced change. Instead of identical DNA in all the cells of the body, somatic mosaicism appears to be the normal human condition. And DNA can no longer be considered the sole agent of inheritance. We now know that the epigenome, which regulates gene expressivity, can be inherited via the germline. These developments are particularly significant for behavior genetics for at least three reasons: First, epigenetic regulation, DNA variability, and somatic mosaicism appear to be particularly prevalent in the human brain and probably are involved in much of human behavior; second, they have important implications for the validity of heritability and gene association studies, the methodologies that largely define the discipline of behavior genetics; and third, they appear to play a critical role in development during the perinatal period and, in particular, in enabling phenotypic plasticity in offspring. I examine one of the central claims to emerge from the use of heritability studies in the behavioral sciences, the principle of minimal shared maternal effects, in light of the growing awareness that the maternal perinatal environment is a critical venue for the exercise of adaptive phenotypic plasticity. This consideration has important implications for both developmental and evolutionary biology.
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Abstract
Although popularly designated as "identical", monozygotic (MZ) twins are rarely identical. Much has been speculated on the origin of MZ twins and several theories have been proposed. Post-fertilization events, such as chromosomal mosaicism, skewed X-inactivation and imprinting mechanisms, as well as other epigenetic mechanisms are responsible for the differences between MZ twins. Numerous discordant MZ twins have been reported including discordance for lateral asymmetry, major malformation, growth and intrauterine death of the co-twin. This discrepancy may have long-term implications on complex diseases and their predisposition, organ transplantation and interpretation of twin-based studies. We reviewed the genotypic and phenotypic differences between MZ twins and discuss their main causes.
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Affiliation(s)
- Sara Silva
- Department of Obstetrics and Gynecology, University Hospital of S. Jo;atao, Medical Faculty of Porto, Porto, Portugal
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