Correct Response: C. The p53 gene regulates cell growth and proliferation by preventing unrestricted cell division. When the p53 gene is deactivated, malfunctioning cells may continue to have unregulated growth and may eventually form tumors. Therapy using the p53 gene targets these malfunctioning cells for apoptosis, or programmed death, thus inhibiting the development of cancerous tumors. Although a predisposition for cancer may be inherited (A), the goal of p53 therapy is to provide a treatment for the malfunctioning cells, not to prevent the inheritance of cancer. The primary function of p53 is to regulate cell growth and proliferation; as such, it is unlikely to have a significant effect in treating polygenic disorders related to cancer (B), nor would it be likely to improve the response of healthy cells to chemotherapy (D).
