(Solved): DNA sequencing of the factor IX gene from a patient with severe hemophilia B shows the presence of ...

DNA sequencing of the factor IX gene from a patient with severe hemophilia B shows the presence of a $$322?bp$$ insert into the fifth exon. This insert is flanked by 6-bp direct repeats with the sequence GGCATG. When the inserted sequence is used to probe a genomic Southern blot of human DNA from a patient who does not have hemophilia $$B$$, the resulting autoradiogram shows a large heterogeneous smear of hybridizing DNA. Which of the following is the most likely cause of the hemophilia in this patient? A) Disruption of the factor IX reading frame by insertion of an Alu sequence B) Infection by a retrovirus C) Insertional activation of a factor IX pseudogene D) Unequal crossing over between factor IX genes