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Hydrops fetalis occurs in the setting of a certain type of thalassemia. What is the underlying mechanism leading to this event?

A) Excess α-globin chains binding tighter to oxygen
(B) Excess α-globin chains binding weaker to oxygen
© Excess β-globin chains binding tighter to oxygen
(D) Excess β-globin chains binding weaker to oxygen
(E) Excess gamma-globin chains binding tighter to oxygen
(F) Excess gamma-globin chains binding weaker to oxygen

E. ty

Hydrops Fetalis=4 alpha chain deletion=Excess gamma globulin=tighter binding to O2
Thank you for the question.

"E" is right......gamma globin tetramers (Hb Barts).....when all 4 α-globin genes are deleted.

You are very welcome

EE
Thanks