Question: 
Describe the following using pRb and retinoblastoma as examples:
1) the two-hit hypothesis for inactivation of a tumor suppressor gene (TSG), and
2) the smart ways by which incipient cancer cells perform the second hit to inactivate the remaining healthy allele of a TSG in order to induce loss of heterozygosity for a TSG.

*** This does not need to have any citations or works cited (obviously should be written without plagiarism). I will email the additional material files, and send a link to the online ebook for this class. Chapters 7 & 8 should contain the answer for this question. Instructions say to refer to only the book and the PowerPoint slides to answer the question.