HEREDITY
THE PEDIGREE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Hemophilia is a recessive sex-linked trait. If H = normal & h = has hemophilia, which genotype represents a male with hemophilia.
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XHY
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XHXh
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XhXh
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XhY
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Explanation:
Detailed explanation-1: -Causes. Variants in the F8 gene cause hemophilia A, while variants in the F9 gene cause hemophilia B. The F8 gene provides instructions for making a protein called coagulation factor VIII.
Detailed explanation-2: -Since the Y chromosome does not carry the hemophilia gene, a son born to a man with hemophilia and a woman who is not a carrier will not have hemophilia. If the baby gets the X chromosome from the father it will be a girl. The X chromosome from the father with hemophilia will have the hemophilia gene.
Detailed explanation-3: -Answer and Explanation: The genotype for a woman with hemophilia will be: XhXh. Where ‘Xh’ means gene carrying the mutation for hemophilia present in the X chromosome.
There is 1 question to complete.