The effects of point mutations within the coding sequence of a gene are discussed in Chapter 19 (refer back to Table 19.1). For each of the following types of point mutations to promote cancer, would you expect the mutation to occur in a proto-oncogene, a tumor-suppressor gene, or either kind of gene?

A. Nonsense mutation 

B. Missense mutation 

C. Frameshift mutation

 Table 19.1:

TABLE 19.1 Consequences of Point Mutations Within a Coding Sequence Type of Change Mutation In the DNA None None Example* Met - Thr - - Pro Asp 5'-A-T-G-A-C-C-G-A-C-C-C-G-A-A-A-G-G-G-A-C-C-3' - Lys - Gly - Thr - Amino Acids Likely Effect on Altered Protein Function None None Silent Base substitution 5-A-T-G-A-C-C Met Thr - - A-C-C-C-C-A-A-A-C -G-A-C-C-3' - Asp ProLys Gly - - Thr None None 5'-A-T-G-C-C-C-G-A-C-C-C-G-A-A-A-G-G-G-A-C-C-3' Missense Base substitution Met - Pro - Asp Pro - Lys-Gly-Thr- - 5'-A-T-G-A-C-C-G-A-C-C-C-G-T-A-A-G-G-G-A-C-C-3' One Neutral or inhibitory Nonsense Base substitution - Met Thr - Asp Pro - STOP! Many Inhibitory Frameshift Addition/deletion 5'-A-T-G-A-C-C-G-A-C- Met Thr Asp - G-A-A-A-G-G-G-A-C-C-3' - Ala - Glu Arg Asp - - Many Inhibitory