Biology 1001A Lecture Notes - Lecture 13: Heterozygote Advantage, Allele Frequency, Genetic Drift
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Bio 1001a - lecture 13 agents of evolution. Changing allele frequencies in heterozygote disadvantage situation (w rr = wss > Wrs: whichever allele has the higher frequency will continue to increase, other allele will decrease until it disappears. Changing allele frequencies in heterozygote advantage situation (wrr = wss < Wrs: both alleles will approach equilibrium frequency of 0. 5. Why the effects of heterozygote advantage vs disadvantage are different. How does the frequency of an allele affect the likelihood that it will occur in a heterozygote rather than a homozygote: if allele is very common (high frequency), it"s found mostly in homozygous individuals. Therefore if there is heterozygote advantage, common alleles will decrease in frequency. Therefore if there is heterozygote disadvantage, that allele will increase in frequency: if allele is rare (low frequency), it"s found mostly in heterozygotes. Therefore if there is heterozygote advantage, that allele will increase in frequency. Therefore if there is heterozygote disadvantage, that allele will disappear.