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Mutagenesis and Genetic
Screens
What is a mutation?
What are the types of
mutations?
Consequences of point mutations
Types of chromosome mutations
What are the consequences of
mutations?
Consequences of point mutations within genes
Figure 15-2
Sequence of the b-globin Gene
Point mutations can alter mRNA splicing
Consequences of point mutations on gene products
How do mutations occur?
Bases may take on rare tautomeric forms prone to mismatch
Bases may take on rare tautomeric forms prone to mismatch
Figure 15-8b
Tautomeric shifts in DNA bases may cause mutations
Indel mutations result in frameshifts
Alternative pairings for 5-bromouracil (5-BU)
Alternative pairings for 2-aminopurine
Alkylation-induced specific mispairings
Figure 15-16
Intercalating agents
Figure 15-17a
Intercalating agents
Figure 15-17b
UV-light-generated photoproducts
Figure 15-18
Trinucleotide repeats in the FMR-1 gene hinder transcription
Slipped mispairing causes repeat expansion
Figure 15-13