BIOL 2040 Lecture Notes - Lecture 3: Gene Duplication, Polyploid, Point Mutation
13 Feb 2016
School
Department
Course
Professor
Document Summary
Mutation: a heritable change in genetic material that is not due to genetic recombination. Introduces variation before any other evolutionary force can act: natural selection unable to operate without a mutation/variability. Point mutation: causes, mutations that create a change in a single base pair. Does not effect previous or subsequent base pairs. A ends up paired with g, rather than t. Random errors in repair following dna damage: transition, transversion. Dna polymerase mistakenly substitutes a purine (a and g) for another purine or a pyrimidine (t and c) for another pyrimidine. Purine is substituted for a pyrimidine, or vice versa. Possible due to redundancy of genetic code. Serious point mutations o: base insertion and deletion cause frame shifts. Every amino acid after insertion/deletion is changed. Point mutation rates: per base pair, per generation = 10^-9. About 1 in 1 000 000 000. There are ~1000 10 000 bases in a gene.
