Effects of Migration and Mutation on Allele Frequencies

Describe the effects of gene migration on allele frequencies

Without any opposing force, migration will tend to equalize gene frequencies among populations.

Lake Erie watersnakes (text)

Describe effect of mutation on allele frequencies

Mutation by itself does not cause appreciable change in gene frequencies

See handout

But, it is engine for selection

E. coli evolution in nutrient poor environments (text)

Describe the mutation/selection balance

Selection acts to eliminate deleterious alleles, but mutation continually creates them.

Spinal muscular atrophy (Text)

Cystic fibrosis allele (text)

Application: analysis of genetic disease. Cystic fibrosis allele - the protein the CF gene codes for