Essential Genetics 6th Edition by Daniel Hartl

Exercise 7

Mutations in the KRAS gene are frequently found in colon cancer. These mutations are always missense mutations, primarily in codons 12 or 61. Mutations in the APC gene are also associated with colon cancer. In this case, however, nonsense and frameshift mutations are frequent and are scattered throughout most of the coding region. From this information, answer the following and explain.
(a) Is KRAS an oncogene or a tumor-suppressor gene?
(b) Is APC an oncogene or a tumor-suppressor gene?