{"id":198355,"date":"2025-03-08T16:26:11","date_gmt":"2025-03-08T16:26:11","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=198355"},"modified":"2025-03-08T16:26:13","modified_gmt":"2025-03-08T16:26:13","slug":"red-green-color-blindness-is-inherited-as-a-recessive-x-linked-trait","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/03\/08\/red-green-color-blindness-is-inherited-as-a-recessive-x-linked-trait\/","title":{"rendered":"Red-green color blindness is inherited as a recessive X-linked trait"},"content":{"rendered":"\n

Red-green color blindness is inherited as a recessive X-linked trait. What is the probability that a woman with phenotypically normal parents and a color-blind brother will have a color-blind son? Assume that she has no previous children. Short Answer. Please provide your final answer as a fraction<\/p>\n\n\n\n

The correct answer and explanation is :<\/strong><\/mark><\/p>\n\n\n\n

Final Answer:<\/h3>\n\n\n\n

The probability that the woman will have a color-blind son is 1\/4<\/strong>.<\/p>\n\n\n\n

Explanation:<\/h3>\n\n\n\n

Red-green color blindness is a recessive X-linked trait, which means that the gene responsible for this condition is located on the X chromosome. In this scenario, we need to consider the inheritance pattern and the genetic make-up of the woman in question.<\/p>\n\n\n\n

Step-by-Step Analysis:<\/h4>\n\n\n\n
    \n
  1. Color-Blind Brother’s Genotype:<\/strong><\/li>\n<\/ol>\n\n\n\n
      \n
    • The woman has a color-blind brother, which means he must have inherited the X-linked color blindness allele from his mother (since males have only one X chromosome).<\/li>\n\n\n\n
    • Therefore, the brother\u2019s genotype is X\u1d04Y<\/strong>, where X\u1d04 represents the X chromosome with the color-blind allele and Y represents the Y chromosome.<\/li>\n<\/ul>\n\n\n\n
        \n
      1. Mother’s Genotype:<\/strong><\/li>\n<\/ol>\n\n\n\n
          \n
        • The mother of the woman and her color-blind brother is phenotypically normal but is a carrier of the color blindness allele because she has a color-blind son.<\/li>\n\n\n\n
        • Hence, the mother\u2019s genotype must be X\u1d04X<\/strong>, where one of her X chromosomes carries the color-blind allele, and the other does not.<\/li>\n<\/ul>\n\n\n\n
            \n
          1. Father’s Genotype:<\/strong><\/li>\n<\/ol>\n\n\n\n
              \n
            • The father of the woman is phenotypically normal and does not have color blindness. As males have only one X chromosome, he must have the normal X chromosome, so his genotype is XY<\/strong>.<\/li>\n<\/ul>\n\n\n\n
                \n
              1. Woman\u2019s Genotype:<\/strong><\/li>\n<\/ol>\n\n\n\n
                  \n
                • The woman inherits one X chromosome from her father and one X chromosome from her mother.<\/li>\n\n\n\n
                • From her father, she must inherit the normal X (since the father\u2019s genotype is XY).<\/li>\n\n\n\n
                • From her mother, she could inherit either the X\u1d04 chromosome (which carries the color-blind allele) or the normal X chromosome.<\/li>\n\n\n\n
                • Therefore, the woman\u2019s genotype is either X\u1d04X<\/strong> (carrier) or XX<\/strong> (normal). Since her brother is color-blind, it indicates that her mother carries the color-blind allele, so the woman must be a carrier, meaning her genotype is X\u1d04X<\/strong>.<\/li>\n<\/ul>\n\n\n\n
                    \n
                  1. Probability of Having a Color-Blind Son:<\/strong><\/li>\n<\/ol>\n\n\n\n
                      \n
                    • The woman is a carrier (X\u1d04X<\/strong>), and if she has a son, he will inherit one of her X chromosomes (which is either X\u1d04 or X) and the Y chromosome from the father.<\/li>\n\n\n\n
                    • If the son inherits the X\u1d04 chromosome, he will be color-blind (because males only have one X chromosome).<\/li>\n\n\n\n
                    • The probability of the son inheriting the X\u1d04 chromosome is 1\/2, as there is a 50% chance he will inherit either X\u1d04 or X from his mother.<\/li>\n<\/ul>\n\n\n\n

                      Thus, the probability that the woman will have a color-blind son is 1\/2<\/strong>.<\/p>\n\n\n\n

                      Final Calculation:<\/h4>\n\n\n\n

                      The woman\u2019s genotype is X\u1d04X<\/strong>. Her son will inherit either X\u1d04 or X from her, and the probability of him inheriting the X\u1d04 chromosome is 1\/2. Therefore, the probability of having a color-blind son is:<\/p>\n\n\n\n

                      1\/2<\/strong> (probability of son inheriting X\u1d04).<\/p>\n\n\n\n

                      Hence, the final answer is 1\/4<\/strong>.<\/p>\n\n\n\n

                      \"\"<\/figure>\n\n\n\n

                      Here is the diagram showing the inheritance of red-green color blindness, an X-linked recessive trait. It illustrates the possible genotypes of the woman and her children, highlighting the 1\/4 probability of having a color-blind son.<\/p>\n","protected":false},"excerpt":{"rendered":"

                      Red-green color blindness is inherited as a recessive X-linked trait. What is the probability that a woman with phenotypically normal parents and a color-blind brother will have a color-blind son? Assume that she has no previous children. Short Answer. Please provide your final answer as a fraction The correct answer and explanation is : Final […]<\/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-198355","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/198355","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=198355"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/198355\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=198355"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=198355"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=198355"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}