genetics of down syndrome pdf

endstream 34 0 obj x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 14Rp�W� Overview Down's syndrome occurs in babies born with extra chromosome 21 material in their cells. endstream 0000052252 00000 n endobj 8 0 obj /Contents 44 0 R>> 0000012050 00000 n stream stream 33 0 obj endobj <>>>] endstream Anatomy; Neurology; Cardiovascular; Dentistry; Oncology; Pharmacology h�b```b``b`e`�� ̀ �@16�\-��D%�ff�3�bG�r͓`j;d[��+UR�4�(��~��%!��PW�pTBB��d��!�7��gJ(zi. x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 12Tp�W� stream � �� <> stream � �T� � �� endobj � �o� endobj 0000010698 00000 n 726 0 obj <> endobj xref 726 33 0000000016 00000 n <> DOWN syndrome (DS) is caused by trisomy 21 and is one of the most common genetic causes of cognitive impairment and congenital abnormalities. endstream There are three main types of Down's syndrome: 0000052291 00000 n /Group <> 11 0 obj This additional genetic material alters the course of development and causes the characteristics associated with Down syndrome. 0000009354 00000 n Parents of children with Down syndrome are often confused by the term genetic disorder because they associate the term with inheritance but have also learned that Down syndrome is not typically inherited. <> 42 0 obj %PDF-1.5 %�� <> /Contents 4 0 R>> About one in every 800 babies is born with Down syndrome. This practice is used to make improvements to humans by manipulating their genetics. x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 14Qp�W� 4^䯘F��VJ��P]�h�B;�gX�. ISBN 978-953-307-631-7, PDF ISBN 978-953-51-6460-9, Published 2011-08-29. 7 0 obj Down syndrome is a genetic syndrome, occurring in from 1 in 650 to 1 in 1000 live births. Regardless of the type of Down syndrome a person may have, all people with Down syndrome have an extra, critical portion of chromosome 21 present in all or some of their cells. � �� <> 0000055282 00000 n endobj endobj stream x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 12Pp�W� stream x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 1�Tp�W� Starting in 1960, the lymphocyte culture of peripheral blood was established. Down syndrome is the most commonly occurring chromosomal condition. 47 0 obj endobj 0000027958 00000 n endobj � �� 0000004574 00000 n endobj This additional genetic material alters the course of development and causes the characteristics associated with Down syndrome. 0000013387 00000 n Since then, the term that has been coined is genetic testing. � �� <> /Contents 16 0 R>> 0000001540 00000 n endstream /Contents 28 0 R>> m1��(��t��@@ �*��.^$|IXcZ��5:E�~�[NP��8�)I��=D��jp��c'�~��PR��L��]��!$#W|�U�;�&�nIl�y*� /Contents 14 0 R>> stream Opitz Award Winner Defines Down Syndrome in Diverse Populations: Research will help clinicians identify patients with Down syndrome in non‐European populations, American Journal of Medical Genetics Part A, 10.1002/ajmg.a.60671, 176, 11, (2233-2234), (2018). <> • Down syndrome (DS) or Down's syndrome, also known as trisomy 21, is a genetic disorder caused by the presence of all or part of a third copy of chromosome 21 • Down syndrome is the most common chromosome abnormality in insan or human beings 4. In 95% of cases, Down syndrome is caused by nondisjunction during cell division, resulting in … While the cause of nondisjunction is � �� This extra genetic material causes the developmental changes and physical features of Down syndrome.Down syndrome varies in severity among individuals, causing lifelong intellectual disability and developmental delays. 0000162112 00000 n It’s this extra genetic material that causes the physical features and developmental delays associated with DS. ��.,��:�iĮ}�p��@Y��k� Bx��J��d} e*)DG�Q?0��T��P��`�:�Q�T�f ��Wu56J��b�!�{M2X��z$B�Z�9�'Y�l��$([Z�'��5��>�(�k�J>yظV�s�[D��f�v�#��|�A�B,C��z��!�^�|��|�ZDv,F�Q��#�uP endstream endobj � �� x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 1�Pp�W� <> 3 0 obj stream � �p� 15 0 obj somal regions, termed “Down syndrome critical regions” (DSCR) a region of 3.8-6.5 Mb on 21q21.22, with ap-proximately 30 genes responsible for the majority of DS phenotypes [15,16]. • Boy with Down syndrome assembling a bookcase 5. Trisomy 21 means there are 3 (tri) copies of chromosome (somy) 21. stream American Academy of Pediatrics Committee on Genetics. <> � � � This chromosomal abnormality usually occurs in egg cells but sometimes also occur in sperm cells. endobj x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 1Wp�W� endobj 0000008007 00000 n <> endobj 14 0 obj 0000131995 00000 n 0000002176 00000 n /Contents 12 0 R>> stream 5 0 obj Health Supervision for Children With Down Syndrome. <> endstream endobj <> endstream � �g� 23 0 obj Down syndrome, in most of the cases, is not inherited. Pediatrics. 2000; V erloes et al. stream � �f� endobj 0000005182 00000 n <> 46 0 obj )-��6�J\$[g��%`g\��`��D�d��s�Z��q��c�={�㡂��~M� �~f��\ѧ�07�d[�Y�㺪��;�e�Ͷ�p�R��d��B��v��/|��}�Kw=T��J��v��9�%�r��wzm��J��:�� 8��%;6Z-��:��ͧ�c��L��O ��:��ul�� +��ۈ��ƛ��s3]�{S��x��i!�>��ݾe�h��RHG ��}9,J��ǫ��Kl-�ޖCg,ꌥ�ǓM��vM��iuGJb��rZNp0 � ��e��ۄ�U��mk�վ��3P:k�!��싁�m��T��wJ�Y��I,��NH�Y�1Y�b�*Z��K�>_�%�έ�=&�W[��?Ү|�=� o*��&/� Wendy L. Hobson-Rohrer, MD, MSPH 2. Thereby screening of handicapped persons on a large scale became possible. endstream 0000001345 00000 n Down syndrome is a chromosomal abnormality characterized by the presence of an extra copy of genetic material on chromosome 21, either in whole (trisomy 21) or part (such as due to translocations).The effects of the extra copy varies greatly from individual to individual, depending on the extent of the extra copy, genetic background, environmental factors, and random chance. The degree of intellectual disability varies from mild to moderate. It is usually associated with physical growth delays, mild to moderate intellectual disability , and characteristic facial features . Down syndrome is a chromosomal condition that is associated with intellectual disability, a characteristic facial appearance, and weak muscle tone (hypotonia) in infancy. <> 0000002721 00000 n <> endobj endobj 9 0 obj endstream stream 18 0 obj 0000003558 00000 n GENETIC TESTING 2 Genetic Testing: Down Syndrome Eugenics is a practice that has come a long way since historical times around World War II. � �� 37 0 obj 44 0 obj x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 1Vp�W� In most cases of Down syndrome, a child gets an extra chromosome 21 — for a total of 47 chromosomes instead of 46. The sequencing of Hsa 21 proved to be an import- 2011;128(2):393–406 [OpenUrl][1][Abstract/FREE Full Text][2] 2. An extra chromosome (chromosome 21) originates in the development of either the sperm or the egg. The additional genetic … stream � �� In the early years, mi toses were analysed after direct preparations of bone marrow cells and long term cell cultures of tissue biopsies. Although the syndrome had been described thous ands of 0000129000 00000 n � �]� endobj x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 14Vp�W� 0000104795 00000 n Down syndrome is a condition in which a person is born with an extra copy of chromosome 21. x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 12Rp�W� Down Syndrome Nearly 5,000 babies are born with Down syndrome in the United States each year.2 This means that 1 in every 733 babies is born with this condition.3 Although parents of any age may have a child with Down syndrome, 80% are born to women under the age of 35.4 NICHCY Disability Fact Sheet #4 June 2010 Definition Down syndrome is the 43 0 obj <> <> /Contents 26 0 R>> x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 1Rp�W� � �� 36 0 obj endstream Down syndrome is a chromosome disorder associated with intellectual disability, a characteristic facial appearance, with small nose and an upward slant to the eyes, and low muscle tone in infancy. <> trailer <<594757F51E244E6EBBA070773901370D>]/Prev 1166125/XRefStm 1345>> startxref 0 %%EOF 758 0 obj <>stream <> stream endobj /Contents 40 0 R>> The three genetic variations include: Trisomy 21– More than 90% of Down syndrome cases are caused by trisomy 21. individual. <> 21 0 obj <> stream 25 0 obj x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 14Wp�W� <> /Contents 6 0 R>> However, the age of the mother may also be a risk factor. endstream <> endstream People with Down syndrome can have physical … This book provides a concise yet comprehensive source of current information on Down syndrome. endstream endstream 6 0 obj During the formation of reproductive cells in a parent, a random event occurs resulting in a chromosome abnormality caused by the condition called Trisomy 21. endstream 20 0 obj 0000165107 00000 n More than 350,000 people are living with Down syndrome in the U.S. Down syndrome affects people of all ages, races, and economic levels. 32 0 obj Genetics of Down Syndrome 7 the metaphase of mitosis. • Down syndrome occurs when an individual has a full or partial extra copy of chromosome 21. <> x��\ݲ�q�?O��TqR;4 � p�[��-U�>��ٙxvV�tt�z��I�0_7@��3s$��r��A��?�ꛇ��4�2��߷~��T��T��y��cU��C��Ƿ��6V��.��K]��0{g��!��Y�N�h��3}}��a��S�6��%߶��w�|?��z�[�4�o��1��_�n�y�_�}��>]��Ǽ��>�j�;�'���G��N�I�4l�9�M,=��q6��|�� }�1��8-�K�1��[��o}Y�j^]r�{^t�]vM�ǩ��5.��ɦش�P��AC��|�� o�@��7.�6��J��R�ktF�g��D��kd�l鈙Z��ˇ0��ny��;{��l��j;��̓}0�� l��! /Contents 32 0 R>> /Contents 38 0 R>> endobj stream x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 1Sp�W� It is the most prevalent genetic dis ease worldwide and the common genetic cause of inte llectual disabilities appearing in about 1 in 400-1500 newbo rns. People with Down syndrome may also be born with various health concerns such as heart defects or digestive abnormalities, as … <> /Contents 30 0 R>> 30 0 obj endobj /Contents 8 0 R>> It's the most common genetic chromosomal disorder and cause of learning disa… endobj /Length 5754 >> endobj <> Lisa Samson-Fang, MD 1. 0000000956 00000 n endstream Down Syndrome Also called: Trisomy 21 Down syndrome is one of the most common genetic conditions, affecting approximately 1 in every 800-1,000 children. /Contents 36 0 R>> Genetics and Etiology of Down Syndrome. 0000001687 00000 n <> x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 14Sp�W� endobj <> 1 0 obj <> endobj <> � �x� x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 14Tp�W� x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 14Pp�W� Explore symptoms, inheritance, genetics … <> /Contents 20 0 R>> 22 0 obj Updated National Birth Prevalence Estimates for Selected Birth Defects in the United States, … Edited by: Subrata Dey. Your goal is to create an informational presentation about your specific genetic disorder. x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 14Up�W� endstream <> Down syndrome, it is estimated that the risk of hav-ing a second child with Down syndrome is about one in 100. 0000016052 00000 n 4 0 obj Additional Down syndrome resource materials for medical professionals and new families (PDF) Genetics education materials for school success How to support children with Down syndrome. endobj Previously a region of 1.6 to 2.5 Mb was recognised as sufficient cause for DS pehnotype [17, 18]. stream � �� 10 0 obj 24 0 obj Down syndrome (DS) is a birth defect with huge medi cal and social costs, caused by trisomy of whole or part of chromosome 21. <> endstream /Contents 10 0 R>> INCIDENCE OF DOWN SYNDROME AND MATERNAL AGE Maternal Age Incidence of Down Syndrome 20 1 in 2000 24 1 in 1300 27 1 in 1050 30 1 in 900 33 1 in 600 36 1 in 300 40 1 in 100 13 0 obj This is largely famous due to Nazi Germany and the desire to create the “master race” (History.com, 2017). !C>��BK�N��E�U��;S`Q}�Q��}H endobj /Contents 42 0 R>> endobj 40 0 obj Down syndrome is a set of mental and physical symptoms that result from having an extra copy of chromosome 21. stream Down syndrome is a genetic disorder, occurring when an individual has all or part of an extra copy of chromosome 21. The incidence of DS is 1 in 800–1000 live births; the total prevalence of DS (number of affected cases in live births, stillbirths, and terminations) appears to be steady or rising (L eonard et al. University of Utah, Salt Lake City, UT 1. /Contents 22 0 R>> endobj endobj 28 0 obj 29 0 obj 38 0 obj x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 1Qp�W� stream Free Medical Books PDF EPUB AZW3 .... Free Medical Books. 0000003332 00000 n <> endstream <> 39 0 obj endstream � �� <> <> <> 1. endobj 0000014721 00000 n 19 0 obj � �^� <> x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 1Up�W� endobj endobj 31 0 obj �Q��Yg��Q\��gl)��6�sPX8@�n~��[��D��K�y/?k-n�u1��m�zz��v��=P��'�ݕs]77mHt?41��w�x7��^�"�� .��D��F�C��XP8�� 0$�h 9��hN�YC~s�m��3~�w��~f�I;`GY)a$�O&A/.�}*r�AgPcR�E�fk@��#[�R$^{V��.��Yw�V��싧]u��p��w��l�`v}0]V�B?��T��$O�вނ��l��3g��#��jw�'��|',��=o��G��Q�pX�nu��[�^��/�M]�U�τ؂UOr��"��`@�ED%�HcH��|M��oq=��8,u>��p�J*K5��7��vX�7�E��ܩ��ÑT�#�8��c��n1�V�6��Gv)��}>{&��1H�G4�JX��S��[��O(F(�7��`:1+�I0��Udt1 "��_$��l:��T�ۛ'Ż(-�"^�W� (��l�Sc�}��u��7�(��@�o��j��Z��]J#��c�jx�S0�j��7�V*�f�'�}b��>��ї�pR_L%9(��w�� Kɂt��OK��T��ȳ��}N˴�o�(��صv�Qr�AB,��)�JvT�@Q(�&�[@0�bVݺW�w�Yq�@ѫA邭�z�ܮ'N�@�� endobj endobj endobj 27 0 obj endobj 35 0 obj 26 0 obj stream 0000004300 00000 n 0000003446 00000 n %PDF-1.4 endobj endobj 0000006761 00000 n Down syndrome or Down's syndrome, also known as trisomy 21, is a genetic disorder caused by the presence of all or part of a third copy of chromosome 21. PART I: A GENERAL OVERVIEW OF DOWN SYNDROME 3 1 Overview of Major Clinical Features 3 Neonatal features 3 Growth 3 Neurodevelopment and cognitive ability 4 Immunity 4 Specific conditions 4 2 General Information About Down Syndrome 5 Incidence 5 Genetics and recurrence risk 5 3 A Mäori Perspective 6 PART II: RECOMMENDED MANAGEMENT OF INFANTS, endobj GENETICS OF DOWN'S SYNDROME. endobj endstream stream /Contents 46 0 R>> endobj Down syndrome is a genetic disorder caused when abnormal cell division results in an extra full or partial copy of chromosome 21. <> stream x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� Pp�W� 0000101820 00000 n 16 0 obj 12 0 obj x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� 1Tp�W� /Contents 34 0 R>> endobj [1] /Contents 24 0 R>> 17 0 obj Down's syndrome is also known as trisomy 21. <> <> Mary E. Coussons-Read, Linda S. Crnic, Behavioral assessment of the Ts65Dn mouse, a model for down syndrome: Altered behavior in the elevated plus maze and open field, Behavior Genetics, 10.1007/BF02361154, 26, 1, (7-13), (1996). <> 0000003837 00000 n endobj 41 0 obj x�3R��2�35W(�*T0P�R0T(�Y@��@QC= P A�J�� Tp�W� <> � �� When the egg and the spe stream 0000044930 00000 n 45 0 obj endobj <>/Group <> /Contents 18 0 R>> STATE OF MARYLAND DHMH Maryland Department of Health and Mental Hygiene Office for Genetics and People with Special Health Care Needs DS-Connect: Registro del síndrome de Down (https://dsconnect.nih.gov) El Registro de síndrome de Down, DS Connect™, respaldado por … Down syndrome can be caused by one of three types of abnormal cell division involving chromosom 21. Ut 1 material that causes the characteristics associated with Down syndrome cases are caused by trisomy 21 presentation your! Tri ) copies of chromosome ( chromosome 21 usually associated with physical growth delays, to. 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