BIOL 222 Lecture 33: DNA Repair
3 Dec 2016
School
Department
Course
Professor
Document Summary
Dbs - non-homologous ends joining: advantage = no sister chromatid needed, disadvantage - small deletions, repair of non-homologous regions. Translesion polymerases: alternative polymerases, can replicate over dna damage, exible active site - more error prone. Can"t detect mismatches: these are used when a cell undergoes a lot of mutation or stress, but needs to replicate or express genes anyway. Dna repair and disease: what do you think happens when a person has a loss of function mutation in one of their dna repair pathways, examples of types of diseases. Xeraderma pigmentosum - ner pathway mutations: freckle-like spots, very sensitive to uv light and more susceptible to skin cancer. Hereditary nonpolyposis colon cancer - mmr pathway mutations: colon cancer susceptibility. Werner syndrome - homologous recombination and telomere maintenance mutations: premature aging. Crispr system: prokaryotic adaptive immune system : memory bank of viral sequences, protects against invading viruses, cas protein.
