Problem:

Question 1: How might the loss of a tumor suppressor gene function yield an outcome that is(at the cell level) indistinguishable from the acquisition of an active oncogene?

Question 2: Mice that are homozygous for a complete deletion of the wild-type gene "T" develop multiple tumors in a variety of tissues very early in life. Gene "T" is most likely

A) an oncogene.

B) an activated oncogene.

C) a proto-oncogene.

D) a dominant tumor suppressor gene.

E) a tumor suppressor gene.

Give reasoning with your answer.