Hemophilia is a sex-linked recessive disorder characterized…
Hemophilia is a sex-linked recessive disorder characterized by the inability to properly form blood clots. Hemophilia is known as the “Royal Disease” because of its presence in the royal families of Europe as a result of its appearance in the children of Queen Victoria. The pedigree above shows the family of Victoria’s daughter Alice. Alice passed hemophilia to the German and Russian imperial families. Alice’s daughter Alix (a carrier of hemophilia) married Tsar Nikolas II of Russia and they had 5 children—4 girls and 1 boy. The boy, Alexis, had hemophilia. The girls were all killed during the Russian revolution and it is unknown whether they were carriers of the disease. What is the probability that all 4 daughters were carriers of hemophilia?