BIOL 1020U Lecture Notes - Lecture 5: Genotype Frequency, Inbreeding Depression, Allele Frequency
Document Summary
Provides a null hypothesis for what happens to gene frequencies between generations in absence of evolution. There are four conditions that must be true: the population must be very large, individuals mate at random, immigration and emigration are zero, mutation is rare or absent. Hardy-weinberg equations: p+q=1 p=frequency of dominant allele q=frequency of recessive allele p^2+2pq+q^2=1. Genotype frequencies in population reflect this relationship p^2=frequency of homozygous dominant genotype. 2pq=frequency of heterozygous genotype q^2= frequency of homozygous recessive genotype. In sexual reproduction, parental genotype frequencies determine allele frequencies in gamete pool. Alleles randomly unite into zygotes forming new genotypes whose frequencies are the product of allele frequencies in the gamete pool. If parent frequencies change, it only takes one generation to reach a new equilibrium. Leads to having a much greater chance of producing a certain pool of alleles since relatives have similar genotypes. Inbreeding depression: offspring produced by relatives have lower fitness.
