{"id":193124,"date":"2025-02-19T05:24:10","date_gmt":"2025-02-19T05:24:10","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=193124"},"modified":"2025-02-19T05:24:12","modified_gmt":"2025-02-19T05:24:12","slug":"phenylketonuria-pku-is-a-disease-that-results-from-a-recessive-gene","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/02\/19\/phenylketonuria-pku-is-a-disease-that-results-from-a-recessive-gene\/","title":{"rendered":"Phenylketonuria (PKU) is a disease that results from a recessive gene"},"content":{"rendered":"\n<p>Phenylketonuria (PKU) is a disease that results from a recessive gene. Two normal parents produce a child with PKU.<br>What is the probability that a sperm from the father will contain the PKU allele?<br>What is the probability that an egg from the mothe contain the PKU allele?<br>1\/2<br>2\/3<br>2\/3<br>3\/4<br>1\/3<br>1\/4<br>3\/4<br>1\/2<br>1\/4<\/p>\n\n\n\n<p><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-6-color\"><strong>The Correct Answer and Explanation is :<\/strong><\/mark><\/p>\n\n\n\n<p>Phenylketonuria (PKU) is a genetic disorder caused by a recessive allele. To understand the probabilities of the parents passing on the PKU allele, we need to explore the genetics behind this condition.<\/p>\n\n\n\n<p>PKU is inherited in an autosomal recessive manner, which means that a person must inherit two copies of the PKU allele (one from each parent) to express the disease. A person with the genotype &#8220;aa&#8221; has PKU, while a person with the genotype &#8220;Aa&#8221; is a carrier (heterozygous), and a person with the genotype &#8220;AA&#8221; does not have the disease and is not a carrier.<\/p>\n\n\n\n<p>In this case, we are told that both parents are normal but have a child with PKU. This means that both parents must be carriers of the PKU allele (genotype &#8220;Aa&#8221;), because two carrier parents (both heterozygous) can have a child with PKU (aa).<\/p>\n\n\n\n<p><strong>To determine the probability of a sperm or egg containing the PKU allele:<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Father&#8217;s sperm:<\/strong><br>The father has the genotype &#8220;Aa,&#8221; meaning he carries one copy of the PKU allele (a) and one normal allele (A). The probability of a sperm cell containing the PKU allele (a) is 1\/2, as half of the sperm will carry the &#8220;A&#8221; allele and the other half will carry the &#8220;a&#8221; allele.<\/li>\n\n\n\n<li><strong>Mother&#8217;s egg:<\/strong><br>Similarly, the mother also has the genotype &#8220;Aa.&#8221; Half of her eggs will carry the &#8220;A&#8221; allele, and half will carry the &#8220;a&#8221; allele. Thus, the probability of an egg containing the PKU allele (a) is also 1\/2.<\/li>\n<\/ol>\n\n\n\n<p><strong>Conclusion:<\/strong><br>The probability that a sperm from the father will contain the PKU allele is 1\/2, and the probability that an egg from the mother will contain the PKU allele is also 1\/2.<\/p>\n\n\n\n<p>Therefore, the correct answer to both questions is <strong>1\/2<\/strong>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Phenylketonuria (PKU) is a disease that results from a recessive gene. Two normal parents produce a child with PKU.What is the probability that a sperm from the father will contain the PKU allele?What is the probability that an egg from the mothe contain the PKU allele?1\/22\/32\/33\/41\/31\/43\/41\/21\/4 The Correct Answer and Explanation is : Phenylketonuria (PKU) [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-193124","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/193124","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=193124"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/193124\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=193124"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=193124"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=193124"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}