Which of the following statements best explain why retroviral vectors for gene therapy may increase the patient risk of developing cancer? a. Activating transcription of the retroviral vector's genes may result in spread of the virus throughout the body. b. Retroviral vectors introduce proteins from the virus that alters control of the host cell's cell cycle. c. Retroviral vectors do not express the genes that were introduced into a patient's cells. d. Integration of the retroviral vector's DNA into the genome may misregulate the expression of genes near the integration site.
