PATHOLOGY MCQ
GENETICS AND DISEASE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Hemophilia is a sex-linked recessive trait. If a man with hemophilia marries a woman who is a carrier for the trait, what are the predicted phenotypes for their children?
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1 carrier male:1 affected male:1 carrier female:1 affected female
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1 carrier male:1 affected male:1 carrier female:1 normal female
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1 normal male:1 affected male:1 carrier female:1 affected female
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1 normal male:1 affected male:1 carrier female:1 normal female
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Explanation:
Detailed explanation-1: -A female who is a carrier has a 50-50 chance that each male child will have hemophilia. There is a 50-50 chance that each female child will be a carrier (Picture 2).
Detailed explanation-2: -If a mother is heterozygous (a carrier) for hemophilia and the father does not have hemophilia, each son has a 1 in 2 (50%) chance of getting his mother’s hemophilia allele and having hemophilia. Each daughter has a 1 in 2 (50%) chance of getting her mother’s hemophilia allele and being heterozygous.
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