• A gene pool consists of all the genes and their different alleles, present in an interbreeding?population
• Some populations of the same species are geographically isolated from each other
  • So?multiple gene pools?can exist for a species
• ?Individuals in a population tend to have?common characteristics?and resemble each other
  • Two geographically-isolated population may have?different characteristics?whilst still being the same species
  • This is one basis for?speciation
• ?A consideration of all the genes (and alleles thereof) in a population is important as that will govern the?genomes of the next generation
  • This collection of genes and alleles is commonly called the gene pool

Calculating allele frequencies

• Allele frequencies are defined as the?relative abundance?of alleles for a particular gene
• Allele frequency is calculated by dividing the number of times the?allele of interest?is observed in a population by the total number of copies of?all the alleles?at that particular genetic locus in the population
  • Allele frequencies are expressed as a?number between 0.0 and 1.0?or as percentages?0 - 100%
    • We can think of this as a?probability?that an allele chosen at random in a given gene will be a particular allele of interest
  • ?The frequencies of all the alleles for a particular gene?must add up to 1

???Step 1: Calculate the sum of the allele frequencies given

???Step 2:?Work out the sum of the remaining allele frequencies

???Step 3:?Apply the 4:1 ratio of albino allele: Himalayan allele given in the question

???Step 4:?Complete the table with these frequencies

Stable gene pools

• Populations retain a?stable?gene pool under the following conditions
  • The population is?large
  • Each individual in the population has an?equal chance of mating
  • That matings are?random
  • There are?no selective pressures?acting upon individuals based on their phenotype
• ?A stable gene pool means that a population is?not evolving