BIO 314 Lecture Notes - Lecture 6: Familial Adenomatous Polyposis, Neural Crest, Microtubule
Document Summary
Chapter 7: tumor suppressor genes: understand what dominance and recessive mean in regard to tumor and normal phenotypes. Normal cell donates tumor suppressor that dominates over cancer. Even with deregulated oncogenic signaling, tumor suppressor pathways will prevent cancer. Cancer cells have lost a growth-inhibitory gene, which is provided when fused with a normal cell: understand what loss-of-function and gain-of-function mutations are. Loss-of-function- recessive allele that doesn"t produce wild type phenotype. Usually can be overcome by presence of one wild type allele. Gain-of-function- dominant allele that produces a new phenotype. Usually overcomes wild type allele: understand the data that knudson used to propose his hypothesis. Knudson hypothesized that increased cancer susceptibility is usually an inherited defect in a tumor suppressor gene. Two successive mutations in the same gene would be required to cause loss of function in a tumor suppressor gene. Sporadic retinal tumor was a lot rarer, unilateral, and didn"t affect future cancer growth.
