{"id":36899,"date":"2018-11-13T18:02:43","date_gmt":"2018-11-13T12:32:43","guid":{"rendered":"https:\/\/blog.forumias.com\/?p=36899"},"modified":"2018-11-13T18:02:43","modified_gmt":"2018-11-13T12:32:43","slug":"gene-editing-an-analysis","status":"publish","type":"post","link":"https:\/\/forumias.com\/blog\/gene-editing-an-analysis\/","title":{"rendered":"Gene Editing: An Analysis"},"content":{"rendered":"<p><strong>Context<\/strong><\/p>\n<p>Scientists recently for the first time succeeded in wiping out an entire population of malaria-carrying mosquitoes in the lab using a gene editing tool to programme their extinction.<\/p>\n<p><strong>What is Gene Editing?<\/strong><\/p>\n<ul>\n<li>Genome editing is the deliberate alteration of a selected DNA sequence in a living cell. It involves editing an organism&#8217;s DNA by altering, removing or adding nucleotides to the genome.<\/li>\n<\/ul>\n<p><strong>How does genome editing work?<\/strong><\/p>\n<ul>\n<li>It involves making cuts at specific DNA sequences with enzymes called<strong> \u2018engineered nucleases\u2019 <\/strong>that can make a double stranded \u201ccut\u201d or a single stranded \u201cnick\u201d in an organism\u2019s DNA.<\/li>\n<li><strong>\u00a0<\/strong>After the DNA has been cut, a modified piece of DNA similar in sequence to the site of the cut is introduced by the enzyme named DNA ligase enzyme.<\/li>\n<li>The cell uses the modified piece of DNA as the template to repair the break, filling the break with a copy of the new DNA.<\/li>\n<\/ul>\n<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-36907\" src=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/dna.jpg?resize=397%2C305&#038;ssl=1\" alt=\"\" width=\"397\" height=\"305\" srcset=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/dna.jpg?w=397&amp;ssl=1 397w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/dna.jpg?resize=150%2C115&amp;ssl=1 150w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/dna.jpg?resize=300%2C230&amp;ssl=1 300w\" sizes=\"auto, (max-width: 397px) 100vw, 397px\" \/><\/p>\n<p><strong>About Genetic Material (DNA and RNA)<\/strong><\/p>\n<ul>\n<li><strong>About DNA: <\/strong>DNA (deoxyribonucleic acid) is the genomic material in cells that contains the genetic information used in the development and functioning of all known living organisms.<\/li>\n<li>Most of the DNA is located in the nucleus, although a small amount can be found in mitochondria (mitochondrial DNA). Within the nucleus of eukaryotic cells, DNA is organized into structures called chromosomes.<\/li>\n<li>The complete set of chromosomes in a cell makes up its genome.<\/li>\n<li>The human genome has approximately 3 billion base pairs of DNA arranged into 46 chromosomes. The information carried by DNA is held in the sequence of pieces of DNA called genes.<\/li>\n<\/ul>\n<p><strong>Difference between organisms altered using gene editing tools and genetically modified organisms (GMO): <\/strong><\/p>\n<ul>\n<li>In GMOs, genes derived from other organisms are added to a target organism to confer the trait of interest. For example, Bt cotton contains a gene from the bacterium called Bacillus thuringiensis, which confers resistance to pink bollworms.<\/li>\n<li>Gene editing employs technologies to edit the host organism\u2019s existing genes, making this the most precise way to elicit a genetic change. This is the key difference between a GMO and a genetically edited organism (GEO).<\/li>\n<li>A GMO contains a piece of foreign DNA while a GEO have its own DNA altered, with no addition of any foreign genes.<\/li>\n<\/ul>\n<p><strong>Genome editing systems<\/strong><\/p>\n<ul>\n<li>There are several different types of engineered nucleases used in genome editing.<\/li>\n<li>They all contain a nuclease part to cut the DNA and a DNA-targeting part to recognise the DNA sequence they cut.<\/li>\n<li>They mainly differ in how they recognise the DNA to cut as follows:\n<ul>\n<li><strong>RNA-based: <\/strong>\u00a0These contain a short sequence of RNA that binds to the target DNA to be cut.<\/li>\n<li><strong>Protein-based:<\/strong> These contain a protein that recognises and binds to the target DNA to be cut.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><strong>CRISPR-Cas9<\/strong><\/p>\n<ul>\n<li>CRISPR-Cas9 (\u2018clustered regularly interspaced short palindromic repeats\u2019) is the most common, cheap and efficient system used for genome editing.<\/li>\n<li>It is the DNA-targeting part of the system which consists of an<strong> RNA <\/strong>\u00a0molecule, or \u2018guide\u2019, designed to bind to specific DNA bases through complementary base-pairing.<\/li>\n<li>Cas9 stands for CRISPR-associated protein 9, and is the nuclease part that cuts the DNA.<\/li>\n<li>CRISPR-Cas9 systems can be produced relatively easily in a laboratory, or obtained in the form of commercially available kits.<\/li>\n<li>It was originally discovered in bacteria that use this system to destroy invading viruses.<\/li>\n<\/ul>\n<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-36906\" src=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/genetic.jpg?resize=624%2C113&#038;ssl=1\" alt=\"\" width=\"624\" height=\"113\" srcset=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/genetic.jpg?w=624&amp;ssl=1 624w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/genetic.jpg?resize=150%2C27&amp;ssl=1 150w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/genetic.jpg?resize=300%2C54&amp;ssl=1 300w\" sizes=\"auto, (max-width: 624px) 100vw, 624px\" \/><\/p>\n<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-36905\" src=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/key.jpg?resize=590%2C336&#038;ssl=1\" alt=\"\" width=\"590\" height=\"336\" srcset=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/key.jpg?w=590&amp;ssl=1 590w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/key.jpg?resize=150%2C85&amp;ssl=1 150w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/key.jpg?resize=300%2C171&amp;ssl=1 300w\" sizes=\"auto, (max-width: 590px) 100vw, 590px\" \/><\/p>\n<p><strong>Applications of Gene Editing: <\/strong><\/p>\n<ul>\n<li>Most uses of genome editing have been in<strong> scientific research<\/strong> for example to investigate models of human disease.<\/li>\n<li>In a process called <strong>somatic gene editing,<\/strong> scientists are exploring ways to treat diseases caused by a single mutated gene such as cystic fibrosis, Huntington\u2019s, and sickle cell disease.<\/li>\n<li>In <strong>germline gene editing<\/strong> sperm, eggs, and early stage embryos are altered to protect a child against inheritable diseases such as diabetes, Alzheimer\u2019s, and forms of cancer.<\/li>\n<li><strong>Gene therapy <\/strong>is an artificial method that introduces DNA into the cells of human body which is used in the replacement of genes that cause medical ill-health and destroys the problem causing genes.<\/li>\n<li>It also helps the body to fight against diseases by adding genes to the human body.<\/li>\n<li><strong>Resurrecting extinct species: <\/strong>Gene editing could even be used to bring back extinct species, or at least parts of them, for example by mixing genes from extinct species back into existing ones.<\/li>\n<li>A group called The Long Now Foundation supports these scientific efforts, and hopes first to bring back the<strong> passenger pigeon<\/strong> and then the <strong>wooly mammoth.<\/strong><\/li>\n<li><strong>Gene drives <\/strong>are being developed in yeast, the fruit fly, and two mosquito species, and could be used to drive a naturally occurring, or introduced, gene for sterility through a population.<\/li>\n<\/ul>\n<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-36904\" src=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/lab.jpg?resize=619%2C186&#038;ssl=1\" alt=\"\" width=\"619\" height=\"186\" srcset=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/lab.jpg?w=619&amp;ssl=1 619w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/lab.jpg?resize=150%2C45&amp;ssl=1 150w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/lab.jpg?resize=300%2C90&amp;ssl=1 300w\" sizes=\"auto, (max-width: 619px) 100vw, 619px\" \/><\/p>\n<ul>\n<li><strong style=\"font-size: 1rem;\">Pest control<\/strong><span style=\"font-size: 1rem;\">: Since all insects have some version of doublesex so gene drive can help in developing new pest control measures.<\/span><\/li>\n<\/ul>\n<ul>\n<li><strong>Control malaria outbreak<\/strong>: Since malaria kills more than 4 lakh people each year worldwide, according to the World Health Organization and this gene drive will be significant in controlling the malarial spread.<\/li>\n<li><strong>Step ahead of traditional practice: <\/strong>Traditional approaches to control mosquitoes especially the use of insecticides is becoming less effective which gene drive can overcome.<\/li>\n<li><strong>Agricultural breeding<\/strong> to create crop varieties with desirable traits like disease resistance, drought tolerance, reduced water consumption without introducing foreign DNA.<\/li>\n<li>It can be used to create <strong>transgenic animals<\/strong> models such as rats, mice, pigs and primates, which will decrease the time and resource consumption compared to traditional methods.<\/li>\n<\/ul>\n<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-36903\" src=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/A.jpg?resize=624%2C112&#038;ssl=1\" alt=\"\" width=\"624\" height=\"112\" srcset=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/A.jpg?w=624&amp;ssl=1 624w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/A.jpg?resize=150%2C27&amp;ssl=1 150w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/A.jpg?resize=300%2C54&amp;ssl=1 300w\" sizes=\"auto, (max-width: 624px) 100vw, 624px\" \/><\/p>\n<ul>\n<li><strong>Crops and livestock <\/strong>(e.g. increasing yield, introducing resistance to disease and pests, tolerance of different environmental conditions).<\/li>\n<li><strong>Industrial biotechnology<\/strong> (e.g. developing \u2018third generation\u2019 biofuels and producing chemicals, materials and pharmaceuticals).<\/li>\n<li><strong>Biomedicine<\/strong> (e.g. pharmaceutical development, xenotransplantation, gene and cell-based therapies, control of insect-borne diseases).<\/li>\n<\/ul>\n<p><strong>Concerns of Gene Editing:<\/strong><\/p>\n<ul>\n<li><strong>Commercial aspect- <\/strong>Gene editing might be used as a tool to make <strong>designer babies <\/strong>by selecting desired traits like intelligence, muscularity, eye color, height, memory etc which will create demographic disparity.<\/li>\n<li><strong>Creation of a superior race- <\/strong>The gene editing can be misused by regimes e.g., soviets tried to procreate a human gorilla which will be the ultimate fighting warrior<\/li>\n<li><strong>Tweaking with nature-<\/strong> Ethicists believe that reproduction is a marvel of nature and it should not be tweaked with.<\/li>\n<li><strong>Safety Concerns: <\/strong>Studies have shown that edited cells can lack a cancer suppressing protein.<\/li>\n<li>Genome editing using CRISPR-Cas9 introduces unexpected off-target effects and <strong>large DNA deletions.<\/strong><\/li>\n<li><strong>Evolution<\/strong> is a natural phenomenon but using gene editing technology a man made phenomenon can have bitter consequences in future.<\/li>\n<li><strong>Threat of extinction:<\/strong> It involves intentional modification of genetic makeup of a species which may lead to its extinction.<\/li>\n<li><strong>Ecological risks: <\/strong>Manipulating and removing natural populations by gene drive may<strong> destroy food webs <\/strong>and shift the behaviour of diseases.<\/li>\n<li><strong>Social risks: <\/strong>It can disrupt agriculture, enabling new weapons to mass extinction of species harmful to humans.<\/li>\n<li><strong>Resistance to gene drive:<\/strong> There are also apprehensions that mosquitoes may develop resistance against gene drive technology like other traditional practices of malarial control.<\/li>\n<\/ul>\n<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-36902\" src=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/crisper.jpg?resize=387%2C592&#038;ssl=1\" alt=\"\" width=\"387\" height=\"592\" srcset=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/crisper.jpg?w=387&amp;ssl=1 387w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/crisper.jpg?resize=98%2C150&amp;ssl=1 98w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/crisper.jpg?resize=196%2C300&amp;ssl=1 196w\" sizes=\"auto, (max-width: 387px) 100vw, 387px\" \/><\/p>\n<p><strong>\u00a0India\u2019s Case:<\/strong><\/p>\n<ul>\n<li>India with huge disease burden has no database available on Indian population with comprehensive information on the diseases common in the country.<\/li>\n<li>To address this issue, National Center for Biotechnology Information (NCBI) has presented<strong> Indian Genetic Disease Database (IGDD)<\/strong>, an integrated and curated repository of growing number of mutation data on common genetic diseases afflicting the Indian populations.<\/li>\n<li>India\u2019s current regulatory architecture for approving novel treatments related to gene editing is ambiguous and assigns overlapping functions to different governmental bodies.<\/li>\n<li>This framework needs to be restructured to optimize trial approval time while addressing safety requirements.<\/li>\n<li><strong>Precision medicine<\/strong>, led by gene-editing research and therapies, need to be promoted through indigenous gene editing research to make such treatments available at affordable prices.<\/li>\n<li>Ease of doing research both basic and clinical stems from streamlined regulations and India now needs to balance safety and \u201ctime to approval\u201d to ensure promotion of such research.<\/li>\n<li>The government also needs to improve infrastructure and access to funds, and spur innovation in gene editing niche to India\u2019s pressing problems in healthcare, research etc.<\/li>\n<\/ul>\n<p><strong>Way Forward<\/strong><\/p>\n<p>The <strong>Nuffield Council on Bioethics<\/strong> has recommended following principles and measures to ensure that genome editing proceeds in ways that are ethically acceptable.<\/p>\n<p><strong>Principles<\/strong><\/p>\n<ul>\n<li>Gene Editing must be intended to secure, and be consistent with, the welfare of the future person.<\/li>\n<li>It should not increase disadvantage, discrimination or division in society.<\/li>\n<\/ul>\n<p><strong>Measures<\/strong><\/p>\n<ul>\n<li>The genome editing interventions should be permitted only after sufficient, broad and inclusive public debate about its use and possible implications<\/li>\n<li>The standards of clinical safety should be established clearly.<\/li>\n<\/ul>\n<ul>\n<li>The risks of adverse effects for individuals, groups and society should be appropriately assessed<\/li>\n<\/ul>\n<ul>\n<li>Gene editing, if permitted, should be strictly regulated (by the regulatory bodies in respective countries)<\/li>\n<li>It should be licensed on a case-by-case basis<\/li>\n<\/ul>\n<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-36901\" src=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/the-1.jpg?resize=606%2C104&#038;ssl=1\" alt=\"\" width=\"606\" height=\"104\" srcset=\"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/the-1.jpg?w=606&amp;ssl=1 606w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/the-1.jpg?resize=150%2C26&amp;ssl=1 150w, https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/the-1.jpg?resize=300%2C51&amp;ssl=1 300w\" sizes=\"auto, (max-width: 606px) 100vw, 606px\" \/><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Context Scientists recently for the first time succeeded in wiping out an entire population of malaria-carrying mosquitoes in the lab using a gene editing tool to programme their extinction. What is Gene Editing? Genome editing is the deliberate alteration of a selected DNA sequence in a living cell. It involves editing an organism&#8217;s DNA by&hellip; <a class=\"more-link\" href=\"https:\/\/forumias.com\/blog\/gene-editing-an-analysis\/\">Continue reading <span class=\"screen-reader-text\">Gene Editing: An Analysis<\/span><\/a><\/p>\n","protected":false},"author":61,"featured_media":36908,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"footnotes":""},"categories":[9],"tags":[],"class_list":["post-36899","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-public","entry"],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/forumias.com\/blog\/wp-content\/uploads\/2018\/11\/gene.jpg?fit=1000%2C668&ssl=1","views":{"total":250,"cached_at":""},"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/posts\/36899","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/users\/61"}],"replies":[{"embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/comments?post=36899"}],"version-history":[{"count":0,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/posts\/36899\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/media\/36908"}],"wp:attachment":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/media?parent=36899"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/categories?post=36899"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/tags?post=36899"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}