Concept explainers
Mutations in an autosomal gene in humans cause a form of hemophilia called von Willebrand disease (vWD). This gene specifies a blood plasma protein cleverly called von Willebrand factor (vWF). vWF stabilizes factor VIII, a blood plasma protein specified by the wild-type hemophilia A gene. Factor VIII is needed to form blood clots. Thus, factor VIII is rapidly destroyed in the absence of vWF.
Which of the following might successfully be employed in the treatment of bleeding episodes in hemophiliac patients? Would the treatments work immediately or only after some delay needed for protein synthesis? Would the treatments have only a short-term or a prolonged effect? Assume that all mutations are null (that is, the mutations result in the complete absence of the protein encoded by the gene) and that the plasma is cell-free.
a. | transfusion of plasma from normal blood into a vWD patient |
b. | transfusion of plasma from a vWD patient into a different vWD patient |
c. | transfusion of plasma from a hemophilia A patient into a vWD patient |
d. | transfusion of plasma from normal blood into a hemophilia A patient |
e. | transfusion of plasma from a vWD patient into a hemophilia A patient |
f. | transfusion of plasma from a hemophilia A patient into a different hemophilia A patient |
g. | injection of purified vWF into a vWD patient |
h. | injection of purified vWF into a hemophilia A patient |
i. | injection of purified factor VIII into a vWD patient |
j. | injection of purified factor VIII into a hemophilia A patient |
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ND STONY BROOK UNIVERSITY LOOSELEAF GENETICS: FROM GENES TO GENOMES
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