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  #1  
Old 04-12-2010
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Default Which enzyme deficiency causing this hemolytic anemia?

Two sisters are diagnosed with hemolytic anemia. Their older brother was previously diagnosed with the same disorder. Two other brothers are asymptomatic. The mother and father are second cousins. Deficiency of which of the following enzymes would be most likely to cause this disorder?

A. Debranching enzyme
B. Glucose-6-phosphatase
C. Glucose-6-phosphate dehydrogenase
D. Muscle phosphorylase
E. Pyruvate kinase
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  #2  
Old 04-12-2010
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Idea! E

Hemolytic anemia in AR is PK deficiency !
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Old 04-13-2010
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Default

oh.... i tot it was C.

i guess u're prolly ryte.
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Old 04-13-2010
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E is the correct answer). Only two enzymes of those
listed in the answer choices specifically cause hemolytic anemiayruvate kinase and glucose-6-phosphate dehydrogenase.G6PDdeficiency is inherited as an X-linked recessive trait, so females would not be affected.pyruvate kinase deficiency is an AR disorder,affecting males and females approximately equally. If this enzyme is deficient, red cells have trouble producing enough ATP to maintain the Na+/K+ pump on the plasma membrane, secondarily causing swelling and lysis.
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Old 04-13-2010
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your answer is rather confusing. The questions states that two sisters have hemolytic anemia, and you state that G6PD is the answer although "as an X-linked recessive trait, so females would not be affected." So how can the answer be C??
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Old 04-13-2010
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Default No he did not say that

Quote:
Originally Posted by HouseWannabe View Post
your answer is rather confusing. The questions states that two sisters have hemolytic anemia, and you state that G6PD is the answer although "as an X-linked recessive trait, so females would not be affected." So how can the answer be C??
He did not say G6PD is the answer. He said Pyruvate Kinase deficiency is the answer.
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Old 04-13-2010
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Quote:
Originally Posted by 13monument View Post
He did not say G6PD is the answer. He said Pyruvate Kinase deficiency is the answer.

samo1 said "Yes .C is the correct answer)"
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Old 04-13-2010
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Quote:
Originally Posted by HouseWannabe View Post
your answer is rather confusing. The questions states that two sisters have hemolytic anemia, and you state that G6PD is the answer although "as an X-linked recessive trait, so females would not be affected." So how can the answer be C??
E is correct.i made a mistake on writing.i corrected it.Thanks
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Old 04-14-2010
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Default thx sam

the explanation was good. i realize this question has been asked before in the kaplan q-bank but i always forget this one.

i remember now. AR is PK def and X-linked G6PDH def!
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