404 Chromosomal abnormalities.pdf - Author of Lecture Collins Felicity(Dr Title of Lecture Chromosome Abnormalities(Problem 5.04 Lecture 6 2017

404 Chromosomal abnormalities.pdf - Author of Lecture...

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COMMONWEALTH OF AUSTRALIA Copyright Regulations 1969 WARNING This material has been reproduced and communicated to you by or on behalf of the University of Sydney pursuant to Part VB of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Author of Lecture: Collins, Felicity (Dr) Title of Lecture: Chromosome Abnormalities (Problem 5.04, Lecture 6, 2017) Do not remove this notice
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5.04 Lecture 6 Chromosome Abnormalities 27 th October, 2017 Dr Felicity Collins Clinical Genetics Unit Medical Genomics Department, RPAH Clinical School Disciplines of Genomics, & Paediatrics and Child Health, Sydney Medical School [email protected]
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Outline Introduction and History Chromosome imbalances Aneuploidy Segmental aneuploidy Copy number variants (CNVs) Trisomies with reference to Trisomy 21 Down syndrome Gene expression in trisomy 21 and phenotypes Nature News website
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Less genes than we thought ……….. ( fewer than nematode worm?) DNA the molecular basis of life Trillions of cells Each cell: 46 human chromosomes 2 meters of DNA 3 billion DNA subunits Bases: A,T,G,C ~ 10,000-20,000 genes code for proteins that perform most life functions
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CHROMOSOME DISORDERS MULTIFACTORIAL DISEASES POLYGENIC DISORDERS CONTIGUOUS GENE SYNDROMES
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History of Down Syndrome First chromosome disorder to be clinically defined (Langdon Down, 1866) First human disorder proven to be chromosomal in origin (Lejeune, 1958) Most common single genetic cause of mental retardation Paradigm for genetic disorders due to copy number variations (CNVs)
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John Langdon Down s son, Reginald Langdon Down, was the first to describe the classical pattern of palmar creases in people with DS Reginald Langdon Down s son -also named John Langdon Down had Down Syndrome He was a man of his time, with great insight compared to many… contemporaries, but with some of the inevitable limitations that are expected when... the means of acquiring knowledge - which we now take for granted - were simply not available. (Owen Conor Ward)
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Trisomy 21 as a model Trisomy 21 has been used as a model of all human disorders that are the result of supernumerary copies of a genomic region
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