Population Genetics

Gene Pool:

  • Individual has genotype: such as AA, Aa, or aa
    individual
    genotype    		 alleles
    A a
    AA 2 0
    Aa 1 1
    aa 0 2

  • "population" is all individuals
    . . -of the same species
    . . -living in a defined geographic area
    . . -and "interacting with one another.
  • population has gene pool:
    alleles
    genotype number A a
    AA 49 98 0
    Aa 42 42 42
    aa 9 0 18
    subtotal - 140 60
    total 100 200
    p 0.70
    q 0.30

    p is the frequency of the 'A' allele in the population
    q is the frequency of the 'a' allele in the population
    p + q = 1.00
    . . -allele frequency is independent of Mendelian dominance

    Populations (or sub-populations) can be compared by their gene pools

  • adaptation is reflected in gene pools differences
    . . -when populations are in different environments
    . . -hypothetically: knowing population response to environment
    . . . may allow predicting response to environmental change
    . . . -a) predict effect of deliberate or inadvertent environmental change
    . . . -b) predict environmental change needed to reverse adverse effect on population


    RETURN TO OUTLINE
    © 2004 Prof. LaFrance, Ancilla College