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Old 10-15-2011
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Genetics Expression of X linked recessive in females?

How a female can get X link recessive disease?
1) could be skewed x link inactivation
2) aneuploidy (Turner Syndrome)
any other possibilities?
also how we can differentiate them in questions?
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Old 10-17-2011
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Answer: Females can get an X-linked recessive disorder, but this is very rare. An abnormal gene on the X chromosome from each parent would be required. For example, the father must have the disease (XabY) & the mother is a carrier (XXab). Then the baby girl will have 50% change to have (XabXab)
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Old 10-18-2011
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Correct Answer Manifesting heterozygotes

Females can very rarely get X-linked recessive diseases. When this happens they are called 'manifesting heterozygotes'.
This is due to the random inactivation of one X chromosome, with the normal one being inactivated. They still have some normal X chromosome activated in some other cells which leads to a milder form of diseases than it is in males.
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Old 10-18-2011
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Lets take example of g6pd deficiency. .. .
If its in mild form than it is due to menifesting heterozygoes(got one abnormal x chromosome and other normal. random inactivation of normal x chromosome greater than abnormal x chromosome leads to disease state. . . . .however not whole x chromosome is inactivated.

If it severe disease. . .than she must inherited both abnormal chromosome. .
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Old 10-18-2011
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nmbe 4 block 2 q6, has same concept .what do u think the answer is?
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