Chapter 23, Problem 8
What is apoptosis, and under what circumstances do cells undergo this process?
Video transcript
How can mutations in non-coding segments of DNA contribute to the development of cancers?
What is the difference between saying that cancer is inherited and saying that the predisposition to cancer is inherited?
As a genetic counselor, you are asked to assess the risk for a couple with a family history of familial adenomatous polyposis (FAP) who are thinking about having children. Neither the husband nor the wife has colorectal cancer, but the husband has a sister with FAP. What is the probability that this couple will have a child with FAP? Are there any tests that you could recommend to help in this assessment?
Define tumor-suppressor genes. Why is a mutated single copy of a tumor-suppressor gene expected to behave as a recessive gene?
Describe the steps by which the TP53 gene responds to DNA damage and/or cellular stress to promote cell-cycle arrest and apoptosis. Given that TP53 is a recessive gene and is not located on the X chromosome, why would people who inherit just one mutant copy of a recessive tumor-suppressor gene be at higher risk of developing cancer than those without the recessive gene?
Part of the Ras protein is associated with the plasma membrane, and part extends into the cytoplasm. How does the Ras protein transmit a signal from outside the cell into the cytoplasm? What happens in cases where the ras gene is mutated?