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Deletion (genetics)
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<h2 id="causes">Causes</h2> <p>Causes include the following: </p> <ul><li>Losses from <a href="/facts/Chromosomal_translocation/MKEwqpQw">translocation</a></li> <li><a href="/facts/Chromosomal_crossover/UKewoPa2">Chromosomal crossovers</a> within a <a href="/facts/Chromosomal_inversion/7oM6D9eE">chromosomal inversion</a></li> <li><a href="/facts/Unequal_crossing_over/p3IQXNbp">Unequal crossing over</a></li> <li>Breaking without rejoining</li></ul> <h2 id="types">Types</h2> <p>Types of deletion include the following: </p> <ul><li>Terminal deletion – a deletion that occurs towards the end of a chromosome.</li> <li>Intercalary/interstitial deletion – a deletion that occurs from the interior of a chromosome.</li> <li>Microdeletion – a relatively small amount of deletion (up to 5Mb that could include a dozen genes).</li></ul> <p>Micro-deletion is usually found in children with physical abnormalities. A large amount of deletion would result in immediate abortion (miscarriage). </p> <h2 id="nomenclature">Nomenclature</h2> <p>The <a href="/facts/International_System_for_Human_Cytogenomic_Nomenclature/lgFyru6e">International System for Human Cytogenomic Nomenclature</a> (ISCN) is an international standard for <a href="/facts/Human_chromosome/FRGf11FC">human chromosome</a> <a href="/facts/Nomenclature/YhTgjjyY">nomenclature</a>, which includes band names, symbols and abbreviated terms used in the description of human chromosome and chromosome abnormalities. Abbreviations include a minus sign (−) for chromosome deletions, and <i>del</i> for deletions of parts of a chromosome.<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a> </p> <h2 id="effects">Effects</h2> <p>Small deletions are less likely to be fatal; large deletions are usually fatal – there are always variations based on which genes are lost. Some medium-sized deletions lead to recognizable human disorders, e.g. <a href="/facts/Williams_syndrome/w5e57BH5">Williams syndrome</a>. </p><p>Deletion of a number of pairs that is not evenly divisible by three will lead to a <a href="/facts/Frameshift_mutation/ncWrMHqm">frameshift mutation</a>, causing all of the <a href="/facts/Codon/zUK0bY1B">codons</a> occurring after the deletion to be read incorrectly during <a href="/facts/Translation_(genetics)/JcPC1rth">translation</a>, producing a severely altered and potentially nonfunctional <a href="/facts/Protein/Jxmagu3E">protein</a>. In contrast, a deletion that is evenly divisible by three is called an <i>in-frame</i> deletion.<a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a> </p><p>Deletions are responsible for an array of genetic disorders, including some cases of male <a href="/facts/Infertility/emky9q8L">infertility</a>, two thirds of cases of <a href="/facts/Duchenne_muscular_dystrophy/VnHhefIk">Duchenne muscular dystrophy</a>,<a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a> and two thirds of cases of <a href="/facts/Cystic_fibrosis/tlNK5BAH">cystic fibrosis</a> (those caused by <a href="/facts/%25CE%2594F508/02a5WJ5n">ΔF508</a>).<a class="footnote-ref" id="fnref:9" href="#fn:9"><sup>9</sup></a> Deletion of part of the short arm of chromosome 5 results in <a href="/facts/Cri_du_chat/xgKJxuyy">Cri du chat</a> syndrome.<a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a> Deletions in the <a href="/facts/Survival_motor_neuron/aqWMNhzT">SMN</a>-encoding gene cause <a href="/facts/Spinal_muscular_atrophy/rBzq7qzU">spinal muscular atrophy</a>, the most common genetic cause of infant death. </p><p>Microdeletions are associated with many different conditions, including Angelman Syndrome, Prader-Willi Syndrome, and DiGeorge Syndrome.<a class="footnote-ref" id="fnref:11" href="#fn:11"><sup>11</sup></a> Some syndromes, including Angelman syndrome and Prader-Willi syndrome, are associated with both microdeletions and genomic imprinting, meaning that same microdeletion can cause two different syndromes depending on which parent the deletion came from.<a class="footnote-ref" id="fnref:12" href="#fn:12"><sup>12</sup></a> </p><p>Recent work suggests that some deletions of highly conserved sequences (CONDELs) may be responsible for the evolutionary differences present among closely related species. Such deletions in humans, referred to as <a href="/facts/HCONDELs/DlI8yW1B">hCONDELs</a>, may be responsible for the anatomical and behavioral differences between humans, <a href="/facts/Common_chimpanzee/JXSpFsHy">chimpanzees</a> and other varieties of mammals like <a href="/facts/Ape/QdTk4pko">ape</a> or <a href="/facts/Monkey/ARjd5RRr">monkeys.</a><a class="footnote-ref" id="fnref:13" href="#fn:13"><sup>13</sup></a> </p><p>Recent comprehensive patient-level classification and quantification of driver events in <a href="/facts/The_Cancer_Genome_Atlas/jVf3pEJS">TCGA</a> cohorts revealed that there are on average 12 driver events per tumor, of which 2.1 are deletions of <a href="/facts/Tumor_suppressor_gene/Awte4S51">tumor suppressors</a>.<a class="footnote-ref" id="fnref:14" href="#fn:14"><sup>14</sup></a> </p> <h2 id="detection">Detection</h2> <p>The introduction of molecular techniques in conjunction with classical cytogenetic methods has in recent years greatly improved the diagnostic potential for chromosomal abnormalities. In particular, microarray-comparative genomic hybridization (CGH) based on the use of BAC clones promises a sensitive strategy for the detection of DNA copy-number changes on a genome-wide scale. The resolution of detection could be as high as >30,000 "bands" and the size of chromosomal deletion detected could as small as 5–20 kb in length.<a class="footnote-ref" id="fnref:15" href="#fn:15"><sup>15</sup></a> Other computation methods were selected to discover <a href="/facts/DNA_sequencing/hsPsNCQW">DNA sequencing</a> deletion errors such as <a href="/facts/End-sequence_profiling/T8fbEmjc">end-sequence profiling</a>.<a class="footnote-ref" id="fnref:16" href="#fn:16"><sup>16</sup></a><a class="footnote-ref" id="fnref:17" href="#fn:17"><sup>17</sup></a> </p> <h2 id="mitochondrial-dna-deletions">Mitochondrial DNA deletions</h2> <p>In the yeast <i><a href="/facts/Saccharomyces_cerevisiae/sX9MGFrz">Saccharomyces cerevisiae</a></i>, the nuclear genes <i><a href="/facts/Rad51/ml7klNxX">Rad51</a></i>p, <i><a href="/facts/Rad52/Ua9Dj4WL">Rad52</a></i>p and <i>Rad59p</i> encode proteins that are necessary for recombinational repair and are employed in the repair of <a href="/facts/DNA_damage_(naturally_occurring)/CjGTLKGl">double strand breaks</a> in <a href="/facts/Mitochondrial_DNA/goC0ex0X">mitochondrial DNA</a>.<a class="footnote-ref" id="fnref:18" href="#fn:18"><sup>18</sup></a> Loss of these proteins decreases the rate of spontaneous DNA deletion events in mitochondria.<a class="footnote-ref" id="fnref:19" href="#fn:19"><sup>19</sup></a> This finding implies that the repair of DNA double-strand breaks by homologous recombination is a step in the formation of mitochondrial DNA deletions. </p> <h2 id="see-also">See also</h2> <ul><li><a href="/facts/Indel/4GbSXrGm">Indel</a></li> <li><a href="/facts/Chromosome_abnormalities/6hL7p0cP">Chromosome abnormalities</a></li> <li><a href="/facts/Null_allele/TomfyMDc">Null allele</a></li> <li><a href="/facts/List_of_genetic_disorders/Vd2v6RTR">List of genetic disorders</a></li> <li><a href="/facts/Medical_genetics/hA6DXds9">Medical genetics</a></li> <li><a href="/facts/Microdeletion_syndrome/6CUKDKBu">Microdeletion syndrome</a></li> <li><a href="/facts/Chromosomal_deletion_syndrome/wzEko8oP">Chromosomal deletion syndrome</a></li> <li><a href="/facts/Insertion_(genetics)/LC827MUs">Insertion (genetics)</a></li> <li><a href="/facts/10q26_deletion/z9aoqzcs">10q26 deletion</a></li></ul> Wikimedia Commons has media related to Deletion (genetics). <h2 id="references">References</h2> <ol> <li id="fn:1"><p>Lewis, R. (2004). Human Genetics: Concepts and Applications (6th ed.). McGraw Hill. ISBN 978-0072951745. <a href="978-0072951745" target="_blank">978-0072951745</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Klug, William S. (2015). Concepts of genetics. Michael R. Cummings, Charlotte A. Spencer, Michael Angelo Palladino (Eleventh ed.). Boston. ISBN 978-0-321-94891-5. OCLC 880404074.{{cite book}}: CS1 maint: location missing publisher (link) <a href="978-0-321-94891-5" target="_blank">978-0-321-94891-5</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>Banavali, Nilesh K. (2013). "Partial Base Flipping is Sufficient for Strand Slippage near DNA Duplex Termini". Journal of the American Chemical Society. 135 (22): 8274–8282. doi:10.1021/ja401573j. PMID 23692220. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>Banavali, Nilesh K. (2013). "Analyzing the Relationship between Single Base Flipping and Strand Slippage near DNA Duplex Termini". The Journal of Physical Chemistry B. 117 (46): 14320–14328. doi:10.1021/jp408957c. PMID 24206351. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>Manjari, Swati R.; Pata, Janice D.; Banavali, Nilesh K. (2014). "Cytosine Unstacking and Strand Slippage at an Insertion–Deletion Mutation Sequence in an Overhang-Containing DNA Duplex". Biochemistry. 53 (23): 3807–3816. doi:10.1021/bi500189g. PMC 4063443. PMID 24854722. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4063443" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4063443</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>"ISCN Symbols and Abbreviated Terms". Coriell Institute for Medical Research. Retrieved 2022-10-27. <a href="https://www.coriell.org/0/sections/support/global/iscn_help.aspx?PgId=263" target="_blank">https://www.coriell.org/0/sections/support/global/iscn_help.aspx?PgId=263</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>LSDB — Controlled vocabulary terms Archived 2011-10-06 at the Wayback Machine at The GEN2PHEN Knowledge Centre. Posted Fri, 08/01/2010. <a href="http://www.gen2phen.org/wiki/lsdb-controlled-vocabulary-terms" target="_blank">http://www.gen2phen.org/wiki/lsdb-controlled-vocabulary-terms</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>Lewis, R. (2004). Human Genetics: Concepts and Applications (6th ed.). McGraw Hill. ISBN 978-0072951745. <a href="978-0072951745" target="_blank">978-0072951745</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>Mitchell, Richard Sheppard; Kumar, Vinay; Robbins, Stanley L.; Abbas, Abul K.; Fausto, Nelson (2007). Robbins basic pathology. Saunders/Elsevier. ISBN 978-1-4160-2973-1. <a href="978-1-4160-2973-1" target="_blank">978-1-4160-2973-1</a> <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> <li id="fn:10"><p>Lewis, R. (2004). Human Genetics: Concepts and Applications (6th ed.). McGraw Hill. ISBN 978-0072951745. <a href="978-0072951745" target="_blank">978-0072951745</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></p></li> <li id="fn:11"><p>Srour, Myriam; Shevell, Michael (2015-01-01), Rosenberg, Roger N.; Pascual, Juan M. (eds.), "Chapter 14 - Global Developmental Delay and Intellectual Disability", Rosenberg's Molecular and Genetic Basis of Neurological and Psychiatric Disease (Fifth Edition), Boston: Academic Press, pp. 151–161, ISBN 978-0-12-410529-4, retrieved 2022-01-07 <a href="978-0-12-410529-4" target="_blank">978-0-12-410529-4</a> <a href="#fnref:11" class="footnote-back-ref">↩</a></p></li> <li id="fn:12"><p>Kalsner, Louisa; Chamberlain, Stormy J. (April 22, 2015). "Prader-Willi, Angelman, and 15q11-q13 duplication syndromes". Pediatric Clinics of North America. 62 (3): 587–606. doi:10.1016/j.pcl.2015.03.004. ISSN 0031-3955. PMC 4449422. PMID 26022164. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4449422" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4449422</a> <a href="#fnref:12" class="footnote-back-ref">↩</a></p></li> <li id="fn:13"><p>McLean CY, Reno PL, Pollen AA, Bassan AI, Capellini TD, Guenther C, Indjeian VB, Lim X, Menke DB, Schaar BT, Wenger AM, Bejerano G, Kingsley DM (March 2011). "Human-specific loss of regulatory DNA and the evolution of human-specific traits". Nature. 471 (7337): 216–9. Bibcode:2011Natur.471..216M. doi:10.1038/nature09774. PMC 3071156. PMID 21390129. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3071156" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3071156</a> <a href="#fnref:13" class="footnote-back-ref">↩</a></p></li> <li id="fn:14"><p>Vyatkin, Alexey D.; Otnyukov, Danila V.; Leonov, Sergey V.; Belikov, Aleksey V. (14 January 2022). "Comprehensive patient-level classification and quantification of driver events in TCGA PanCanAtlas cohorts". PLOS Genetics. 18 (1): e1009996. doi:10.1371/journal.pgen.1009996. PMC 8759692. PMID 35030162. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8759692" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8759692</a> <a href="#fnref:14" class="footnote-back-ref">↩</a></p></li> <li id="fn:15"><p>Ren, H (May 2005). "BAC-based PCR fragment microarray: high-resolution detection of chromosomal deletion and duplication breakpoints". Human Mutation. 25 (5): 476–482. doi:10.1002/humu.20164. PMID 15832308. S2CID 28030180. <a href="https://doi.org/10.1002%2Fhumu.20164" target="_blank">https://doi.org/10.1002%2Fhumu.20164</a> <a href="#fnref:15" class="footnote-back-ref">↩</a></p></li> <li id="fn:16"><p>Shmilovici, A.; Ben-Gal, I. (2007). "Using a VOM Model for Reconstructing Potential Coding Regions in EST Sequences" (PDF). Journal of Computational Statistics. 22 (1): 49–69. doi:10.1007/s00180-007-0021-8. S2CID 2737235. Archived from the original (PDF) on 2020-05-31. Retrieved 2014-01-10. <a href="https://web.archive.org/web/20200531014400/http://www.eng.tau.ac.il/~bengal/VOM_EST.pdf" target="_blank">https://web.archive.org/web/20200531014400/http://www.eng.tau.ac.il/~bengal/VOM_EST.pdf</a> <a href="#fnref:16" class="footnote-back-ref">↩</a></p></li> <li id="fn:17"><p>Volik, S.; Zhao, S.; Chin, K.; Brebner, J. H.; Herndon, D. R.; Tao, Q.; Kowbel, D.; Huang, G.; Lapuk, A.; Kuo, W.-L.; Magrane, G.; de Jong, P.; Gray, J. W.; Collins, C. (4 June 2003). "End-sequence profiling: Sequence-based analysis of aberrant genomes". Proceedings of the National Academy of Sciences. 100 (13): 7696–7701. Bibcode:2003PNAS..100.7696V. doi:10.1073/pnas.1232418100. PMC 164650. PMID 12788976. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC164650" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC164650</a> <a href="#fnref:17" class="footnote-back-ref">↩</a></p></li> <li id="fn:18"><p>Ivanetich, K. M.; Lucas, S.; Marsh, J. A.; Ziman, M. R.; Katz, I. D.; Bradshaw, J. J. (1978). "Organic compounds. Their interaction with and degradation of hepatic microsomal drug-metabolizing enzymes in vitro". Drug Metabolism and Disposition: The Biological Fate of Chemicals. 6 (3): 218–225. PMID 26540. <a href="/wiki/PMID_(identifier)" target="_blank">/wiki/PMID_(identifier)</a> <a href="#fnref:18" class="footnote-back-ref">↩</a></p></li> <li id="fn:19"><p>Ivanetich, K. M.; Lucas, S.; Marsh, J. A.; Ziman, M. R.; Katz, I. D.; Bradshaw, J. J. (1978). "Organic compounds. Their interaction with and degradation of hepatic microsomal drug-metabolizing enzymes in vitro". Drug Metabolism and Disposition: The Biological Fate of Chemicals. 6 (3): 218–225. PMID 26540. <a href="/wiki/PMID_(identifier)" target="_blank">/wiki/PMID_(identifier)</a> <a href="#fnref:19" class="footnote-back-ref">↩</a></p></li> </ol>