Question

Answer 1

In the given statements, the statement " Retinoblastoma results from an oncogene and a mutant tumor -suppressor gene, both of which are necessary for cancer to develop " best describes the Alfred Knudson's two hit hypothesis.

The Knudson hypothesis, also known as the two-hit hypothesis was first formulated byAlfred G. Knudson in 1971 and led indirectly to the identification of cancer-related genes. Knudson won the 1998 Albert Lasker Clinical Medical Research Award for this work.

Knudson's hypothesis refers specifically, however, to the heterozygosity of tumor suppressor genes. A mutation in both alleles is required, as a single functional tumor suppressor gene is usually sufficient.