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Discussion Starter · #1 ·
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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Discussion Starter · #4 ·
E is the correct answer). Only two enzymes of those
listed in the answer choices specifically cause hemolytic anemia:pyruvate 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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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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No he did not say that

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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Discussion Starter · #8 ·
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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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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