{"id":31463,"date":"2025-03-25T06:30:28","date_gmt":"2025-03-25T01:00:28","guid":{"rendered":"https:\/\/vajiramandravi.com\/current-affairs\/?p=31463"},"modified":"2025-04-16T12:10:10","modified_gmt":"2025-04-16T06:40:10","slug":"dna-polymorphism","status":"publish","type":"post","link":"https:\/\/vajiramandravi.com\/current-affairs\/dna-polymorphism\/","title":{"rendered":"DNA Polymorphism"},"content":{"rendered":"<h2>DNA Polymorphism Latest News<\/h2>\n<p>DNA polymorphisms, through STR analysis and PCR, enable forensic breakthroughs in justice (exonerations, crime-solving) and historical revelations via ancient DNA extraction.<\/p>\n<h2>What is DNA?<\/h2>\n<ul>\n<li><strong>DNA (Deoxyribonucleic Acid)<\/strong> is the genetic material present in almost <strong>all cells of the human body<\/strong> (skin, blood, bone, teeth, etc.).<\/li>\n<li>Humans have <strong>46 DNA molecules (chromosomes)<\/strong>:\n<ul>\n<li><strong>23 chromosomes inherited from the father<\/strong> (via sperm).<\/li>\n<li><strong>23 chromosomes inherited from the mother<\/strong> (via the egg).<\/li>\n<\/ul>\n<\/li>\n<li><strong>Chromosomes contain genes<\/strong>, which carry <strong>instructions for traits<\/strong> like eye color, height, and susceptibility to diseases.<\/li>\n<\/ul>\n<h2>What are DNA Polymorphisms?<\/h2>\n<ul>\n<li>DNA polymorphisms are <strong>variations in DNA sequences<\/strong> among individuals.<\/li>\n<li>These <strong>genetic differences<\/strong> occur at specific locations in DNA and help differentiate one person from another.<\/li>\n<li>DNA polymorphisms allow scientists to determine:\n<ul>\n<li><strong>Parentage <\/strong>(paternal\/maternal lineage).<\/li>\n<li><strong>Genetic ancestry.<\/strong><\/li>\n<li><strong>Identity verification<\/strong> through DNA fingerprinting.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h2>What are Short Tandem Repeats (STRs)?<\/h2>\n<ul>\n<li><strong>STRs are short sequences of DNA bases (A, T, C, G) that repeat multiple times<\/strong>.<\/li>\n<li>Ex: A repeated sequence like <strong>GATCGATCGATC<\/strong> (on the complementary strand, <strong>CTAGCTAGCTAG<\/strong>).<\/li>\n<li><strong>Each person has a unique STR pattern<\/strong>, making STRs highly useful for:\n<ul>\n<li>Forensic investigations.<\/li>\n<li>Criminal identification.<\/li>\n<li>Parent-child relationship testing.<\/li>\n<\/ul>\n<\/li>\n<li><strong>STRs are inherited<\/strong>, so they provide valuable insights into ancestry and genetic inheritance.<\/li>\n<\/ul>\n<h2>How is DNA Copied for Analysis? (PCR Method)<\/h2>\n<ul>\n<li><strong>Polymerase Chain Reaction (PCR)<\/strong> is a technique used to <strong>amplify DNA segments<\/strong>, making millions of copies.<\/li>\n<li>Steps of PCR:\n<ul>\n<li><strong>DNA Extraction<\/strong>: Scientists collect DNA from blood, bones, saliva, or skin cells.<\/li>\n<li><strong>Denaturation (95\u00b0C)<\/strong>: DNA strands are <strong>heated to separate them<\/strong>.<\/li>\n<li><strong>Annealing (60\u00b0C)<\/strong>: Short DNA <strong>primers bind to target sequences<\/strong>.<\/li>\n<li><strong>Extension (72\u00b0C)<\/strong>: <strong>DNA polymerase enzyme adds complementary bases<\/strong>, creating new DNA strands.<\/li>\n<li><strong>Cycling Process<\/strong>: The steps are repeated, rapidly increasing the DNA copies.<\/li>\n<\/ul>\n<\/li>\n<li>PCR is essential for <strong>DNA fingerprinting, criminal investigations, <\/strong>and <strong>medical research.<\/strong><\/li>\n<\/ul>\n<h2>What is a DNA Fingerprint?<\/h2>\n<ul>\n<li>A <strong>DNA fingerprint is a unique genetic profile<\/strong> based on STR variations.<\/li>\n<li>It is created using <strong>Capillary Electrophoresis<\/strong>:\n<ul>\n<li>DNA fragments move through a capillary under an <strong>electric field<\/strong>.<\/li>\n<li><strong>Smaller fragments travel faster<\/strong>, separating different STR patterns.<\/li>\n<li>The <strong>final DNA profile is unique to each person<\/strong> (except identical twins).<\/li>\n<\/ul>\n<\/li>\n<li><strong>Sources of DNA for fingerprinting<\/strong>: Teeth, bones, blood, saliva, sweat, semen, skin cells.<\/li>\n<\/ul>\n<h2>DNA Polymorphism FAQs<\/h2>\n<p><strong>Q1. <\/strong>What is DNA polymorphism?<\/p>\n<p><strong>Ans.<\/strong> DNA polymorphism refers to variations in DNA sequences among individuals in a population. These variations are heritable and can be used for genetic studies.<\/p>\n<p><strong>Q2. <\/strong>Why is DNA polymorphism important?<\/p>\n<p><strong>Ans.<\/strong> DNA polymorphism is crucial for genetic diversity, disease studies, forensic investigations, and evolutionary biology. It helps in DNA fingerprinting, ancestry tracking, and understanding hereditary diseases.<\/p>\n<p><strong>Q3. <\/strong>How is DNA polymorphism used in forensic science?<\/p>\n<p><strong>Ans.<\/strong> DNA polymorphism, especially STRs and VNTRs, is used in forensic DNA fingerprinting to identify individuals, solve crimes, and establish paternity.<\/p>\n<p><strong>Q4. <\/strong>What is the role of DNA polymorphism in evolution?<\/p>\n<p><strong>Ans.<\/strong> It provides genetic variation, which is essential for natural selection and adaptation. Mutations leading to polymorphism can influence traits and species survival.<\/p>\n<p><strong>Source: <\/strong><a href=\"https:\/\/www.thehindu.com\/sci-tech\/science\/what-are-dna-polymorphisms-and-how-do-they-differentiate-between-people\/article69369159.ece\" target=\"_blank\" rel=\"nofollow noopener\">TH<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>DNA polymorphism refers to heritable variations in DNA sequences among individuals, aiding genetic studies, evolution research, &#038; disease analysis.<\/p>\n","protected":false},"author":5,"featured_media":31464,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[],"class_list":{"0":"post-31463","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-upsc-prelims-current-affairs","8":"no-featured-image-padding"},"acf":[],"_links":{"self":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/31463","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/comments?post=31463"}],"version-history":[{"count":0,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/31463\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media\/31464"}],"wp:attachment":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media?parent=31463"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/categories?post=31463"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/tags?post=31463"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}