Zusammenfassung der Ressource
Population genetics; the Hardy-Weinberg principle
- Gene pool; is the sum of all the alleles in a population. The members
of each population, therefore have the same gene pool.
- Allele frequency; refers to the population or percentage of a particular
allele of a gene in a population, relative to other alleles of the same
gene.
- The Hardy-Weinberg equation; is an equation to calculate allele and
genotype frequencies within a population
- p = represents the frequency of the dominant allele,
q = represents the frequency of the recessive allele,
p + q =1.0
- However in diploid organisms alleles occur in pairs. In order
to calculate genotype frequency rather than allele frequency,
a second equation is used; p2 + 2pq + q2 = 1.0
- where; p2 = frequency of the AA genotype, 2pq = frequency
of the Aa genotype, q2 = frequency of aa genotype
- The Hardy-Weinberg priciple; the frequency of dominant and
recessive alleles in a popuation will remain constant from generation
to generation provided certain conditions are met, these are;
- 1. The population is large
- 2. Mating is random
- 3. No mutations occur
- 4. There is no immigration into or emmigration out of the population
- 5. All genotypes are equally fertile so that no natural selection is taking place
- The name given to a change in allele frequency due to change is called genetic drift