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Old 05-30-2011
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Question mucopolysaccharidosis Type II & genetics

Hunter syndrome, or mucopolysaccharidosis Type II, is a rare disease that it shows X-linked recessive inheritance. In a female with 2 brothers with the diasese, which of the following is correct?

a) The probability that she is a carrier is 2/3.
b) If she is a carrier then the probability that each of her sons will be affected is 1 in 4.
c) If she is a carrier then the probability that each of her daughters will be a carrier is 1 in 4.
d) Before any carrier testing is carried out the woman can be correctly informed that the probability that her first son will be affected is 1 in 4.
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Old 05-30-2011
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no idea which one is the right answer...

the probability that her son will be affected is 1 in 2
the probability that her daughter will be carrier is 1 in 2
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Old 05-30-2011
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Im stuck between A) and C)

What's with the recent flux of genetics questions?
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Old 05-30-2011
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Pls keep genetic calculation coming, the more the better!
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Old 05-30-2011
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a) The probability that she is a carrier is 2/3.---should be 1/2
b) If she is a carrier then the probability that each of her sons will be affected is 1 in 4.---if she's a carrier, Xx, then son will be 1/2 chance to have dz
c) If she is a carrier then the probability that each of her daughters will be a carrier is 1 in 4.--daughter would be 1/2 carrier
d) Before any carrier testing is carried out the woman can be correctly informed that the probability that her first son will be affected is 1 in 4.--this one is right. possibility to be a carrier 1/2, transfer the bad one to don is 1/2, so 1/2*1/2=1/4
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Old 05-30-2011
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Quote:
Originally Posted by 123to789 View Post
a) The probability that she is a carrier is 2/3.---should be 1/2
b) If she is a carrier then the probability that each of her sons will be affected is 1 in 4.---if she's a carrier, Xx, then son will be 1/2 chance to have dz
c) If she is a carrier then the probability that each of her daughters will be a carrier is 1 in 4.--daughter would be 1/2 carrier
d) Before any carrier testing is carried out the woman can be correctly informed that the probability that her first son will be affected is 1 in 4.--this one is right. possibility to be a carrier 1/2, transfer the bad one to don is 1/2, so 1/2*1/2=1/4
you´re absolutely right. Thanks!
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Biochemistry-, Genetics-, Syndromes-Acronyms

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