{"corpus_id":23024653,"paper_sha":"3b14fda1515ebac052bb6567fda8bd05094dcd6d","doi":"10.1126/SCIENCE.1251186","arxiv_id":null,"pmid":1251186,"pmcid":null,"mag_id":2078769454,"dblp_id":null,"acl_id":null,"title":"Evolution of repeated DNA sequences by unequal crossover.","year":1976,"publication_date":"1976-02-13","venue":"Science","journal":{"name":"Science","pages":"\n          528-35\n        ","volume":"191 4227"},"journal_issn":null,"journal_title":null,"publication_types":["JournalArticle"],"pubmed_pub_types":["Journal Article","Research Support, U.S. Gov't, P.H.S."],"s2_fields_of_study":["Biology","Medicine"],"reference_count":22,"citation_count":1163,"influential_citation_count":36,"is_open_access":false,"arxiv_categories":null,"arxiv_license":null,"arxiv_journal_ref":null,"mesh_headings":[{"d":"Animals","mj":false,"ui":"D000818"},{"d":"Base Sequence","mj":false,"ui":"D001483"},{"d":"Biological Evolution","mj":true,"ui":"D005075"},{"d":"Chromatids","mj":false,"ui":"D002842"},{"d":"Computers","mj":false,"ui":"D003201"},{"d":"Crossing Over, Genetic","mj":true,"ui":"D003434"},{"d":"DNA","mj":true,"ui":"D004247"},{"d":"DNA, Satellite","mj":true,"ui":"D004276"},{"d":"Genes","mj":false,"ui":"D005796"},{"d":"Models, Biological","mj":false,"ui":"D008954"},{"d":"Mutation","mj":false,"ui":"D009154"},{"d":"RNA, Ribosomal","mj":false,"ui":"D012335"}],"chemicals":[{"n":"DNA, Satellite","ui":"D004276","reg":"0"},{"n":"RNA, Ribosomal","ui":"D012335","reg":"0"},{"n":"DNA","ui":"D004247","reg":"9007-49-2"}],"comments_corrections":null,"source_flags":5,"s2_open_access_pdf_url":null,"s2_open_access_landing_url":null,"s2_open_access_license":null,"s2_open_access_status":null,"pmc_open_access_pdf_url":null,"pmc_open_access_landing_url":null,"pmc_open_access_license":null,"pmc_open_access_status":null,"unpaywall_open_access_pdf_url":null,"unpaywall_open_access_landing_url":null,"unpaywall_open_access_license":null,"unpaywall_open_access_status":null,"abstract":"It is often supposed that highly repetitious DNA's arise only as a result of unusual mechanisms or in response to selective pressure. My arguments and simulations suggest, by contrast, that a pattern of tandem repeats is the natural state of DNA whose sequence is not maintained by selection. The simulations show that periodicities can develop readily from nonreptitious DNA as a result of the random accumulation of random mutations and random homology-dependent unequal crossovers. The lengths of these periodicities, and the patterns of subrepeats within them, would fluctuate in evolution, with the probability of a given pattern being dependent on the unknown exact nature of the crossover mechanism. Qualitatively, then, unequal crossover provides a reasonable and uncontrived explanation for the prevalence of highly repeated sequences in DNA and for the patterns of periodicity they evince.","claims":[{"public_id":"cl_d6ecca505989f26d9c3bbb6732a9780f","status":"active","text":"A pattern of tandem repeats is presented as the natural state of DNA whose sequence is not maintained by selection.","confidence":0.96,"contributors":[{"id":391,"public_id":"x53qfq3ny9","public_label":"kafkapple (x53qfq3ny9)","roles":["extraction"],"url":"https://sah.borca.ai/u/x53qfq3ny9"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1,"public_id":"12632b8b5f","public_label":"Anonymous (12632b8b5f)","roles":["review"],"url":"https://sah.borca.ai/u/12632b8b5f"}],"url":"https://sah.borca.ai/claims/cl_d6ecca505989f26d9c3bbb6732a9780f"},{"public_id":"cl_d300cda79156629e3be2badfa2de5cd1","status":"active","text":"Periodicities 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