Down's Syndrome Phenotype and Autosomal Gene Inactivation in a Child with Presumed
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Combinatorial Genomic Data Refute the Human Chromosome 2 Evolutionary Fusion and Build a Model of Functional Design for Interstitial Telomeric Repeats
The Proceedings of the International Conference on Creationism Volume 8 Print Reference: Pages 222-228 Article 32 2018 Combinatorial Genomic Data Refute the Human Chromosome 2 Evolutionary Fusion and Build a Model of Functional Design for Interstitial Telomeric Repeats Jeffrey P. Tomkins Institute for Creation Research Follow this and additional works at: https://digitalcommons.cedarville.edu/icc_proceedings Part of the Biology Commons, and the Genomics Commons DigitalCommons@Cedarville provides a publication platform for fully open access journals, which means that all articles are available on the Internet to all users immediately upon publication. However, the opinions and sentiments expressed by the authors of articles published in our journals do not necessarily indicate the endorsement or reflect the views of DigitalCommons@Cedarville, the Centennial Library, or Cedarville University and its employees. The authors are solely responsible for the content of their work. Please address questions to [email protected]. Browse the contents of this volume of The Proceedings of the International Conference on Creationism. Recommended Citation Tomkins, J.P. 2018. Combinatorial genomic data refute the human chromosome 2 evolutionary fusion and build a model of functional design for interstitial telomeric repeats. In Proceedings of the Eighth International Conference on Creationism, ed. J.H. Whitmore, pp. 222–228. Pittsburgh, Pennsylvania: Creation Science Fellowship. Tomkins, J.P. 2018. Combinatorial genomic data refute the human chromosome 2 evolutionary fusion and build a model of functional design for interstitial telomeric repeats. In Proceedings of the Eighth International Conference on Creationism, ed. J.H. Whitmore, pp. 222–228. Pittsburgh, Pennsylvania: Creation Science Fellowship. COMBINATORIAL GENOMIC DATA REFUTE THE HUMAN CHROMOSOME 2 EVOLUTIONARY FUSION AND BUILD A MODEL OF FUNCTIONAL DESIGN FOR INTERSTITIAL TELOMERIC REPEATS Jeffrey P. -
Ring 21 FTNW
Ring 21 rarechromo.org Sources Ring 21 The information Ring 21 is a rare genetic condition caused by having a in this leaflet ring-shaped chromosome. comes from the Almost half of the people with ring 21 chromosomes medical literature described in the medical literature are healthy and and from develop normally. Their unusual chromosomes are Unique’s discovered by chance, during tests for infertility or after members with repeated miscarriages or after having an affected baby. Ring 21 In other people the ring 21 chromosome affects (referenced U), development and learning and can also cause medical who were problems. In most of these people these effects are surveyed in slight but in some people they can be severe. The 2004. Unique is effects can even vary between different members of the very grateful to same family. The reason for these differences is not yet the families who fully understood. took part in the survey. What is a chromosome? The human body is made up of cells. Inside most cells is References a nucleus where genetic information is stored in genes which are grouped along chromosomes. Chromosomes The text contains are large enough to be studied under a microscope and references to come in different sizes, each with a short (p) and a long articles published (q) arm. They are numbered from largest to smallest in the medical according to their size, from number 1 to number 22, in press. The first- addition to the sex chromosomes, X and Y. A normal, named author healthy cell in the body has 46 chromosomes, 23 from and publication the mother and 23 from the father, including one date are given to chromosome 21 from each parent. -
Epigenetic Control of Mammalian Centromere Protein Binding: Does DNA Methylation Have a Role?
Journal of Cell Science 109, 2199-2206 (1996) 2199 Printed in Great Britain © The Company of Biologists Limited 1996 JCS3386 Epigenetic control of mammalian centromere protein binding: does DNA methylation have a role? Arthur R. Mitchell*, Peter Jeppesen, Linda Nicol†, Harris Morrison and David Kipling MRC Human Genetics Unit, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK *Author for correspondence (internet [email protected]) †Present address: MRC Reproductive Biology Unit, Edinburgh, UK SUMMARY Chromosome 1 of the inbred mouse strain DBA/2 has a block of minor satellite DNA sequences on chromosome 1. polymorphism associated with the minor satellite DNA at The binding of the CENP-E protein does not appear to be its centromere. The more terminal block of satellite DNA affected by demethylation of the minor satellite sequences. sequences on this chromosome acts as the centromere as We present a model to explain these observations. This shown by the binding of CREST ACA serum, anti-CENP- model may also indicate the mechanism by which the B and anti-CENP-E polyclonal sera. Demethylation of the CENP-B protein recognises specific sites within the arrays minor satellite DNA sequences accomplished by growing of minor satellite DNA on mouse chromosomes. cells in the presence of the drug 5-aza-2′-deoxycytidine results in a redistribution of the CENP-B protein. This protein now binds to an enlarged area on the more terminal Key words: Centromere satellite DNA, Demethylation, Centromere block and in addition it now binds to the more internal antibody INTRODUCTION A common feature of many mammalian pericentromeric domains is that they contain families of repetitive DNA The centromere of mammalian chromosomes is recognised at sequences (Singer, 1982). -
The 50Th Anniversary of the Discovery of Trisomy 21: the Past, Present, and Future of Research and Treatment of Down Syndrome
REVIEW The 50th anniversary of the discovery of trisomy 21: The past, present, and future of research and treatment of Down syndrome Andre´Me´garbane´, MD, PhD1,2, Aime´ Ravel, MD1, Clotilde Mircher, MD1, Franck Sturtz, MD, PhD1,3, Yann Grattau, MD1, Marie-Odile Rethore´, MD1, Jean-Maurice Delabar, PhD4, and William C. Mobley, MD, PhD5 Abstract: Trisomy 21 or Down syndrome is a chromosomal disorder HISTORICAL REVIEW resulting from the presence of all or part of an extra Chromosome 21. Clinical description It is a common birth defect, the most frequent and most recognizable By examining artifacts from the Tumaco-La Tolita culture, form of mental retardation, appearing in about 1 of every 700 newborns. which existed on the border between current Colombia and Although the syndrome had been described thousands of years before, Ecuador approximately 2500 years ago, Bernal and Briceno2 it was named after John Langdon Down who reported its clinical suspected that certain figurines depicted individuals with Tri- description in 1866. The suspected association of Down syndrome with somy 21, making these potteries the earliest evidence for the a chromosomal abnormality was confirmed by Lejeune et al. in 1959. existence of the syndrome. Martinez-Frias3 identified the syn- Fifty years after the discovery of the origin of Down syndrome, the term drome in a terra-cotta head from the Tolteca culture of Mexico “mongolism” is still inappropriately used; persons with Down syn- in 500 patients with AD in which the facial features of Trisomy drome are still institutionalized. Health problems associated with that 21 are clearly displayed. -
Biol 1020: Chromosomal Genetics
Ch. 15: Chromosomal Abnormalities Abnormalities in Chromosomal Number Abnormalities in Chromosomal Structure: Rearrangements Fragile Sites . • Define: – nondisjunction – polyploidy – aneupoidy – trisomy – monosomy . Abnormalities in chromosomal number How does it happen? . Abnormalities in chromosomal number nondisjunction - mistake in cell division where chromosomes do not separate properly in anaphase usually in meiosis, although in mitosis occasionally in meiosis, can occur in anaphase I or II . Abnormalities in chromosomal number polyploidy – complete extra sets (3n, etc.) – fatal in humans, most animals aneuploidy – missing one copy or have an extra copy of a single chromosome three copies of a chromosome in your somatic cells: trisomy one copy of a chromosome in your somatic cells: monosomy most trisomies and monosomies are lethal well before birth in humans; exceptions will be covered . Abnormalities in chromosomal number generally, in humans autosomal aneuploids tend to be spontaneously aborted over 1/5 of human pregnancies are lost spontaneously after implantation (probably closer to 1/3) chromosomal abnormalities are the leading known cause of pregnancy loss data indicate that minimum 10-15% of conceptions have a chromosomal abnormality at least 95% of these conceptions spontaneously abort (often without being noticed) . • Define: – nondisjunction – polyploidy – aneupoidy – trisomy – monosomy . • Describe each of the aneuploidies that can be found in an appreciable number of human adults (chromosomal abnormality, common name of the syndrome if it has one, phenotypes) . aneuploidy in human sex chromosomes X_ female (Turner syndrome) short stature; sterile (immature sex organs); often reduced mental abilities about 1 in 2500 human female births XXY male (Klinefelter syndrome) often not detected until puberty, when female body characteristics develop sterile; sometimes reduced mental abilities; testosterone shots can be used as a partial treatment; about 1 in 500 human male births . -
Evolution on the X Chromosome: Unusual Patterns and Processes
REVIEWS Evolution on the X chromosome: unusual patterns and processes Beatriz Vicoso and Brian Charlesworth Abstract | Although the X chromosome is usually similar to the autosomes in size and cytogenetic appearance, theoretical models predict that its hemizygosity in males may cause unusual patterns of evolution. The sequencing of several genomes has indeed revealed differences between the X chromosome and the autosomes in the rates of gene divergence, patterns of gene expression and rates of gene movement between chromosomes. A better understanding of these patterns should provide valuable information on the evolution of genes located on the X chromosome. It could also suggest solutions to more general problems in molecular evolution, such as detecting selection and estimating mutational effects on fitness. Haldane’s rule Sex-chromosome systems have evolved independently the predictions of theoretical models of X-chromosome The disproportionate loss of many times, and have attracted much attention from evolution will shed light on the assumptions on which fitness to the heterogametic evolutionary geneticists. This work has mainly focused the models are based, such as the degree of dominance of sex in F1 hybrids between on the steps leading to the initial evolution of sex chro- mutations and the existence of opposing forces species. mosomes, and the genetic degeneration of Y and W of selection on males and females, leading to a better 1 Clade chromosomes . Here, we discuss the evolution of the understanding of the forces that shape the evolution of A group of species which share X chromosome in long-established sex-chromosome eukaryotic genomes. a common ancestor. -
1311.Full.Pdf
Copyright © 2005 by the Genetics Society of America DOI: 10.1534/genetics.104.033167 Chromosome Loss Followed by Duplication Is the Major Mechanism of Spontaneous Mating-Type Locus Homozygosis in Candida albicans Wei Wu, Claude Pujol, Shawn R. Lockhart and David R. Soll1 Department of Biological Sciences, University of Iowa, Iowa City, Iowa 52242 Manuscript received July 7, 2004 Accepted for publication December 7, 2004 ABSTRACT Candida albicans, which is diploid, possesses a single mating-type (MTL) locus on chromosome 5, which is normally heterozygous (a/␣). To mate, C. albicans must undergo MTL homozygosis to a/a or ␣/␣. Three possible mechanisms may be used in this process, mitotic recombination, gene conversion, or loss of one chromosome 5 homolog, followed by duplication of the retained homolog. To distinguish among these mechanisms, 16 spontaneous a/a and ␣/␣ derivatives were cloned from four natural a/␣ strains, P37037, P37039, P75063, and P34048, grown on nutrient agar. Eighteen polymorphic (heterozygous) markers were identified on chromosome 5, 6 to the left and 12 to the right of the MTL locus. These markers were then analyzed in MTL-homozygous derivatives of the four natural a/␣ strains to distinguish among the three mechanisms of homozygosis. An analysis of polymorphisms on chromosomes 1, 2, and R excluded meiosis as a mechanism of MTL homozygosis. The results demonstrate that while mitotic recombination was the mechanism for homozygosis in one offspring, loss of one chromosome 5 homolog followed by duplication of the retained homolog was the mechanism in the remaining 15 offspring, indicating that the latter mechanism is the most common in the spontaneous generation of MTL homozy- gotes in natural strains of C. -
Dr. Fern Tsien, Dept. of Genetics, LSUHSC, NO, LA Down Syndrome
COMMON TYPES OF CHROMOSOME ABNORMALITIES Dr. Fern Tsien, Dept. of Genetics, LSUHSC, NO, LA A. Trisomy: instead of having the normal two copies of each chromosome, an individual has three of a particular chromosome. Which chromosome is trisomic determines the type and severity of the disorder. Down syndrome or Trisomy 21, is the most common trisomy, occurring in 1 per 800 births (about 3,400) a year in the United States. It is one of the most common genetic birth defects. According to the National Down Syndrome Society, there are more than 400,000 individuals with Down syndrome in the United States. Patients with Down syndrome have three copies of their 21 chromosomes instead of the normal two. The major clinical features of Down syndrome patients include low muscle tone, small stature, an upward slant to the eyes, a single deep crease across the center of the palm, mental retardation, and physical abnormalities, including heart and intestinal defects, and increased risk of leukemia. Every person with Down syndrome is a unique individual and may possess these characteristics to different degrees. Down syndrome patients Karyotype of a male patient with trisomy 21 What are the causes of Down syndrome? • 95% of all Down syndrome patients have a trisomy due to nondisjunction before fertilization • 1-2% have a mosaic karyotype due to nondisjunction after fertilization • 3-4% are due to a translocation 1. Nondisjunction refers to the failure of chromosomes to separate during cell division in the formation of the egg, sperm, or the fetus, causing an abnormal number of chromosomes. As a result, the baby may have an extra chromosome (trisomy). -
Continuous Variation in Y-Chromosome Structure of Rumex Acetosa
Heredity 57 (1986) 247-254 The Genetical Society of Great Britain Received 16 December 1985 Continuous variation in Y-chromosome structure of Rumex acetosa A. S. Wilby and School of Biological Sciences, J. S. Parker Queen Mary College, Mile End Road, London El 4NS. The dioecious angiosperm Rumex acetosa has an XXIXY1Y2sex-chromosomesystem. Each V-chromosome is heterochromatic except for a minute terminal euchromatic pairing segment. The Vs are constant in size but have a variable centromere position. The centromeres can be located anywhere within the central 40 per cent of the chromosome but are excluded from the two distal 30 per cent regions. In a sample of 270 males from 18 different populations 68 distinct variants have been identified on the basis of V-morphology. All populations are highly polymorphic with a minimum of four variants in a sample of ten males. The origin and significance of this massive variability is considered in this paper. Increased mutation rate of the Ys may be implicated in maintenance of this variation. I NTRO DUCTI ON these "inert" Ys has been described (Vana, 1972) variation in their structure has been overlooked. Sex-determinationin animals is usually genic and Extensive heterochroinatic content is a charac- frequently associated with visibly-differentiated teristic of many Y- and W-chromosomes. Indeed, sex-chromosomes. Sex expression in plants, some have argued that the process of hetero- however, is usually more plastic, and is subject to chromatinisation itself was implicated in the initial environmental influences such as temperature and phase of sex-chromosome differentiation (Jones, photoperiod (Heslop-Harrison, 1957). -
Chromosome 2 Introduction the Genetic Length of Chromosome 2
Chromosome 2 ©Chromosome Disorder Outreach Inc. (CDO) Technical genetic content provided by Dr. Iosif Lurie, M.D. Ph.D Medical Geneticist and CDO Medical Consultant/Advisor. Ideogram courtesy of the University of Washington Department of Pathology: ©1994 David Adler.hum_02.gif Introduction The genetic length of chromosome 2 spans ~237 Mb. It is ~8% of the whole human genetic material. The length of the short arm is ~89 Mb; the length of the long arm is 148 Mb. Chromosome 2 contains ~1500 genes. At least 200 of these genes are related to different kinds of genetic pathologies. Many of these genes are associated with structural defects of the organs, and others, to functional defects. The numerous structural abnormalities of chromosome 2 had already been reported before methods of molecular genetics gained wide usage. Currently there are ~1,500 reports on patients with varying structural abnormalities of this chromosome, including ~1,000 reports on patients with deletions. Deletions have been reported in at least 10–15 patients for each segment of chromosome 2. There are ten known syndromes caused by deletions of chromosome 2, including three syndromes related to deletions of the short arm (p). Some of these syndromes have been known for many years; others (del 2p15p16.1, del 2q23q24, and del 2q32) have been delineated only in the last couple of years. Deletions of Chromosome 2 Different types of chromosome 2 deletions have been described in numerous publications and may be subdivided into 3 groups: • Deletions that are “harmless” variants (usually familial) • Unique deletions that have not been categorized as a syndrome yet • Deletions that are considered a syndrome Deletions of 2p Deletion of 2p15p16.1 This syndrome, first described in 2007, is rare; only ten patienys have been described to date. -
Detailed Genetic and Physical Map of the 3P Chromosome Region Surrounding the Familial Renal Cell Carcinoma Chromosome Translocation, T(3;8)(Pl4.2;Q24.1)1
[CANCER RESEARCH 53. 3118-3124. July I. 1993] Detailed Genetic and Physical Map of the 3p Chromosome Region Surrounding the Familial Renal Cell Carcinoma Chromosome Translocation, t(3;8)(pl4.2;q24.1)1 Sal LaForgia,2 Jerzy Lasota, Parida Latif, Leslie Boghosian-Sell, Kumar Kastury, Masataka Olita, Teresa Druck, Lakshmi Atchison, Linda A. Cannizzaro, Gilad Barnea, Joseph Schlessinger, William Modi, Igor Kuzmin, Kaiman Tory, Berton Zbar, Carlo M. Croce, Michael Lerman, and Kay Huebner3 Jefferson Cancer Institute. Thomas Jefferson Medical College. Philadelphia, Pennsylvania 19107 (S. L. J. L. L B-S.. K. K.. M. O.. T. D.. L A. C.. C. M. C.. K. H.I: Laboratory of Immunobiology. National Cancer Institute. Frederick Cancer Research and Development Center. Frederick. Maryland 21701 (F. L, l. K.. K. T.. B. Z.. M. L): Biological Carcinogenesis and Development Program. Program Resources Inc./Dyn Corp.. Frederick Cancer Research and Development Center. Frederick. Maryland 21701 1W. M.Õ: Chestnut Hill College. Philadelphia. Pennsylvania 19118 (L A.): and Department oj Pharmacology. New York University. New York. New York 10012 (G. B., J. S.I ABSTRACT location of the critical 3p region(s) harboring the target gene(s) had been hampered by the paucity of well-localized, widely available Extensive studies of loss of heterozygosity of 3p markers in renal cell molecular probes. Recently, efforts to isolate and localize large num carcinomas (RCCs) have established that there are at least three regions bers of 3p molecular probes have been undertaken (25-28). As the critical in kidney tumorigenesis, one most likely coincident with the von Hippel-Lindau gene at 3p25.3, one in 3p21 which may also be critical in probe density on 3p increased, in parallel with recent LOH studies, it small cell lung carcinomas, and one in 3pl3-pl4.2, a region which includes became clear that multiple independent loci on 3p were involved the 3p chromosome translocation break of familial RCC with the t(3;8)- (summarized in Refs. -
Cytogenetics, Chromosomal Genetics
Cytogenetics Chromosomal Genetics Sophie Dahoun Service de Génétique Médicale, HUG Geneva, Switzerland [email protected] Training Course in Sexual and Reproductive Health Research Geneva 2010 Cytogenetics is the branch of genetics that correlates the structure, number, and behaviour of chromosomes with heredity and diseases Conventional cytogenetics Molecular cytogenetics Molecular Biology I. Karyotype Definition Chromosomal Banding Resolution limits Nomenclature The metaphasic chromosome telomeres p arm q arm G-banded Human Karyotype Tjio & Levan 1956 Karyotype: The characterization of the chromosomal complement of an individual's cell, including number, form, and size of the chromosomes. A photomicrograph of chromosomes arranged according to a standard classification. A chromosome banding pattern is comprised of alternating light and dark stripes, or bands, that appear along its length after being stained with a dye. A unique banding pattern is used to identify each chromosome Chromosome banding techniques and staining Giemsa has become the most commonly used stain in cytogenetic analysis. Most G-banding techniques require pretreating the chromosomes with a proteolytic enzyme such as trypsin. G- banding preferentially stains the regions of DNA that are rich in adenine and thymine. R-banding involves pretreating cells with a hot salt solution that denatures DNA that is rich in adenine and thymine. The chromosomes are then stained with Giemsa. C-banding stains areas of heterochromatin, which are tightly packed and contain