BSC 315 Lecture 28: 19
Document Summary
Population genetic terms: population: a group of breeding individuals, population genetics: allele frequencies in populations and mechanisms of change over time, evolution: change in allele frequency within a population over time. Calculating allele frequencies: a static view of allele frequency: the hardy-weinberg equation, imagine gene with alleles a and a, 36% have genotype a/a (recessive phenotype). Hardy-weinberg equilibrium: hardy-weinberg equilibrium: the population is stable and allele frequencies do not change over time. If so, allele frequencies can be calculated using the h-w equation. Assumptions: no migration, no mutation, mating is random, populations infinitely large, no selection, since all are never true, h-w is an approximation. Hw can be expanded to 3 or more alleles: example: ia, ib and i alleles for blood type. Many genes in human populations are in hw equilibrium: most loci tested are in hw equilibrium, practical importance: applicability of codis database.