Lect_6_MutationVariation

Lect_6_MutationVariation

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Measuring MUTATION rates Measuring MUTATION rates Measuring MUTATION rates How are muta6on rates measured? Main obstacles: - - muta6ons are rare (average < 1 x 10- 9 per site per replica6on) many sites and replica/ons must be observed to es/mate rate - - many muta6ons are highly deleterious not observed because mutants are removed by selec/on Main approaches: - - screen for phenotypes resul6ng from known muta6on - ability to produce a specific required nutrient in bacteria - appearance of human achondroplas6c dwarfism - decline in fitness in muta6on accumula6on experiments - - grow strains, sequence DNA of descendants and compare sequences - requires a lot of sequencing but this is possible now due to advances in sequencing technology Measuring MUTATION rates Measuring MUTATION rates Measuring MUTATION rates Some muta6ons are more likely than other—just based on the chemistry… Measuring MUTATION rates IMPORTANCE OF GENOME SIZE. Es6mates of spontaneous muta6on rates per base pair and per genome TABLE 8.2 " " " "per base pair " " "per haploid genome humans "5.0 x 10-11 " " "0.16 E. coli " "2.4 x 10-8 " " "0.0040 Why do humans have a lower per base muta6on rate than E. coli but a higher genomic muta6on rate? Measuring MUTATION rates IMPORTANCE OF POPULATION SIZE (N): Muta6on rates seem low….but lots of varia6on can be generated each genera6on: For example, in humans: 5x10- 11 muta6ons / base pair /genera6on, (haploid genome size is 3.2 x...
View Full Document

This note was uploaded on 02/10/2014 for the course ECOL 335 taught by Professor Reinthal during the Spring '10 term at University of Arizona- Tucson.

Ask a homework question - tutors are online