{"id":4457,"date":"2026-07-09T15:05:10","date_gmt":"2026-07-09T12:05:10","guid":{"rendered":"https:\/\/letgenbio.com\/?p=4457"},"modified":"2026-07-09T15:16:50","modified_gmt":"2026-07-09T12:16:50","slug":"petos-paradox-why-do-large-animals-get-less-cancer-than-expected","status":"publish","type":"post","link":"https:\/\/letgenbio.com\/en\/petos-paradox-why-do-large-animals-get-less-cancer-than-expected\/","title":{"rendered":"Peto&#8217;s Paradox: Why Do Large Animals Get Less Cancer Than Expected?"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"4457\" class=\"elementor elementor-4457\">\n\t\t\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-8b9d78c ts-col-stretched-none ts-bg-color-over-image elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"8b9d78c\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-a4b2519 ts-bg-color-over-image\" data-id=\"a4b2519\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-c25d5a8 elementor-widget elementor-widget-text-editor\" data-id=\"c25d5a8\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p class=\"isSelectedEnd\">First described by epidemiologist Richard Peto in 1977, Peto&#8217;s Paradox raises one of the most intriguing questions in biology:<\/p><p class=\"isSelectedEnd\"><strong>Why don&#8217;t organisms with more cells and longer lifespans have higher-than-expected rates of cancer?<\/strong><\/p><p>In theory, as the number of cells increases, so does the probability of DNA replication errors that can lead to cancer. However, the incidence of cancer in elephants, whales, and other large mammals does not match this expectation. This is because these species have evolved powerful tumor-suppressive mechanisms that help protect them against cancer.<\/p><p class=\"isSelectedEnd\"><strong>Cancer Protection Mechanisms in Elephants<\/strong><\/p><p class=\"isSelectedEnd\">Compared with humans, elephants have approximately 20 times more copies of the <strong>TP53<\/strong> gene. Known as the <strong>&#8220;guardian of the genome,&#8221;<\/strong> TP53 detects DNA damage, halts the cell cycle, promotes DNA repair, and, when necessary, directs damaged cells to undergo apoptosis.<\/p><p class=\"isSelectedEnd\">In addition, the <strong>LIF6 (Leukemia Inhibitory Factor 6)<\/strong> gene found in elephants contributes to the rapid elimination of cells carrying severe DNA damage, thereby reducing the risk of cancer development.<\/p><p class=\"isSelectedEnd\">Similarly, in blue whales and other large marine mammals, the activity of tumor suppressor genes such as <strong>PTEN<\/strong> and <strong>CDKN2A<\/strong> is particularly noteworthy. These genes help maintain genomic stability by regulating cell proliferation.<\/p><p class=\"isSelectedEnd\"><strong>Why Is It Important for Cancer Research?<\/strong><\/p><p>Understanding the molecular mechanisms underlying Peto&#8217;s Paradox may contribute to a better understanding of cancer biology in humans and support the development of new diagnostic and therapeutic strategies.<\/p><p class=\"isSelectedEnd\">In particular, investigating the regulatory mechanisms of genes such as <strong>TP53, LIF6, PTEN,<\/strong> and <strong>CDKN2A<\/strong> represents an important area of research for the development of targeted therapies, biomarkers, and early diagnostic approaches.<\/p><p>In addition, <strong>liquid biopsy<\/strong> technologies based on the analysis of <strong>cell-free DNA (cfDNA)<\/strong> and <strong>microRNAs (miRNAs)<\/strong> are playing an increasingly important role in the early detection of cancer, monitoring treatment response, and assessing minimal residual disease.<\/p><h5>Support Your Cancer Research with Letgen Biotechnology<\/h5><p class=\"isSelectedEnd\">Reliable cancer research depends on high-quality sample preparation, sensitive analysis, and the right molecular tools.<\/p><p class=\"isSelectedEnd\">At Letgen Biotechnology, we provide researchers with the following solutions:<\/p><ul data-spread=\"false\"><li><strong>Norgen cf-DNA Preservation Tubes:<\/strong> Ensure the stable preservation of cell-free DNA during sample collection and transportation.<\/li><li><strong>Roche Digital PCR Systems:<\/strong> Enable highly sensitive detection of low-frequency tumor biomarkers and support minimal residual disease (MRD) studies.<\/li><li><strong>Norgen RNA\/DNA Isolation Kits:<\/strong> Provide high-quality nucleic acid isolation from a variety of sample types, including tissue, plasma, and cell cultures.<\/li><li><strong>NGS and Bioinformatics Services:<\/strong> Enable comprehensive analysis of genetic variants, gene expression profiles, and molecular pathways.<\/li><\/ul>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-562f9cb ts-col-stretched-none ts-bg-color-over-image elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"562f9cb\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-442bed6 ts-bg-color-over-image\" data-id=\"442bed6\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-25010ca elementor-widget elementor-widget-text-editor\" data-id=\"25010ca\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>Discover Letgen Biotechnology&#8217;s solutions to support your cancer research with advanced molecular technologies.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-26a4e04 elementor-widget elementor-widget-image\" data-id=\"26a4e04\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img fetchpriority=\"high\" decoding=\"async\" width=\"847\" height=\"443\" src=\"https:\/\/letgenbio.com\/wp-content\/uploads\/2026\/07\/Petos-Paradox-Commercial-1024x536.png\" class=\"attachment-large size-large wp-image-4461\" alt=\"\" srcset=\"https:\/\/letgenbio.com\/wp-content\/uploads\/2026\/07\/Petos-Paradox-Commercial-1024x536.png 1024w, https:\/\/letgenbio.com\/wp-content\/uploads\/2026\/07\/Petos-Paradox-Commercial-300x157.png 300w, https:\/\/letgenbio.com\/wp-content\/uploads\/2026\/07\/Petos-Paradox-Commercial-768x402.png 768w, https:\/\/letgenbio.com\/wp-content\/uploads\/2026\/07\/Petos-Paradox-Commercial.png 1200w\" sizes=\"(max-width: 847px) 100vw, 847px\" data-id=\"4461\" title=\"\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-3c138ff ts-col-stretched-none ts-bg-color-over-image elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"3c138ff\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-16e49ff ts-bg-color-over-image\" data-id=\"16e49ff\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-84c1bf2 elementor-widget elementor-widget-text-editor\" data-id=\"84c1bf2\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p class=\"MsoNormal\" style=\"text-align: justify;\">Don&#8217;t forget to follow us and subscribe for the latest biotechnology news and industry insights!<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0faa32c elementor-widget elementor-widget-image\" data-id=\"0faa32c\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img decoding=\"async\" width=\"552\" height=\"384\" src=\"https:\/\/letgenbio.com\/wp-content\/uploads\/2026\/07\/Adsiz-tasarim-15.png\" class=\"attachment-1536x1536 size-1536x1536 wp-image-4450\" alt=\"\" srcset=\"https:\/\/letgenbio.com\/wp-content\/uploads\/2026\/07\/Adsiz-tasarim-15.png 552w, https:\/\/letgenbio.com\/wp-content\/uploads\/2026\/07\/Adsiz-tasarim-15-300x209.png 300w\" sizes=\"(max-width: 552px) 100vw, 552px\" data-id=\"4450\" title=\"\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-07dacfe ts-col-stretched-none ts-bg-color-over-image elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"07dacfe\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-0d9b4b0 ts-bg-color-over-image\" data-id=\"0d9b4b0\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-6c73cd5 elementor-widget elementor-widget-text-editor\" data-id=\"6c73cd5\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p class=\"MsoNormal\" style=\"text-align: justify;\">Resources:<\/p><ol style=\"margin-top: 0cm;\" start=\"1\" type=\"1\"><li class=\"MsoNormal\" style=\"text-align: justify; mso-list: l0 level1 lfo1; tab-stops: list 36.0pt;\">Peto, R. (2015). Quantitative implications of the approximate irrelevance of mammalian body size and lifespan to lifelong cancer risk. Philosophical Transactions of the Royal Society B: Biological Sciences, 370(1673), 20150198.<\/li><li class=\"MsoNormal\" style=\"text-align: justify; mso-list: l0 level1 lfo1; tab-stops: list 36.0pt;\">Abegglen, L. M., et al. (2015). Potential Mechanisms for Cancer Resistance in Elephants and Comparative Cellular Response to DNA Damage in Humans. JAMA, 314(17), 1850\u20131860.<\/li><li class=\"MsoNormal\" style=\"text-align: justify; mso-list: l0 level1 lfo1; tab-stops: list 36.0pt;\">Tollis, M., Schiffman, J. D., &amp; Boddy, A. M. (2017). Evolution of cancer suppression as revealed by mammalian comparative genomics. Current Opinion in Genetics &amp; Development, 42, 40-47.<\/li><\/ol>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>First described by epidemiologist Richard Peto in 1977, Peto&#8217;s Paradox raises one of the most intriguing questions in biology: Why don&#8217;t organisms with more cells and longer lifespans have higher-than-expected rates of cancer? In theory, as the number of cells increases, so does the probability of DNA replication errors that can lead to cancer. However, &hellip; <a href=\"https:\/\/letgenbio.com\/en\/petos-paradox-why-do-large-animals-get-less-cancer-than-expected\/\" class=\"more-link\" title=\"Continue reading <span class=\"screen-reader-text\">Peto&#8217;s Paradox: Why Do Large Animals Get Less Cancer Than Expected?<\/span>&#8220;>Continue reading <span class=\"screen-reader-text\">Peto&#8217;s Paradox: Why Do Large Animals Get Less Cancer Than Expected?<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":4458,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-4457","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-genel"],"_links":{"self":[{"href":"https:\/\/letgenbio.com\/en\/wp-json\/wp\/v2\/posts\/4457","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/letgenbio.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/letgenbio.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/letgenbio.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/letgenbio.com\/en\/wp-json\/wp\/v2\/comments?post=4457"}],"version-history":[{"count":4,"href":"https:\/\/letgenbio.com\/en\/wp-json\/wp\/v2\/posts\/4457\/revisions"}],"predecessor-version":[{"id":4465,"href":"https:\/\/letgenbio.com\/en\/wp-json\/wp\/v2\/posts\/4457\/revisions\/4465"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/letgenbio.com\/en\/wp-json\/wp\/v2\/media\/4458"}],"wp:attachment":[{"href":"https:\/\/letgenbio.com\/en\/wp-json\/wp\/v2\/media?parent=4457"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/letgenbio.com\/en\/wp-json\/wp\/v2\/categories?post=4457"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/letgenbio.com\/en\/wp-json\/wp\/v2\/tags?post=4457"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}