Download Hardy-Weinberg Equation Notes

WARM UP
1. Describe how the different
blood types affect how blood
transfusions can be given.
What blood types can give or
receive blood with other
types?
Hardy-Weinberg Equation
Hardy-Weinberg Rule
• G.H. Hardy
– British mathematicican
• Wilhelm Weinberg
– German doctor
• Analyze allele frequencies to see if a
population is evolving
H-W Equation
• p2 + 2pq + q2 = 1
– p = A frequency
q = a frequency
• p+q=1
– p2 = AA
q2 = aa
H-W Equation
• To solve for allele frequencies:
– Find frequency of aa organisms
• aa freq. = q2
– Square root of q2 = q
• q = a frequency
–1–q=p
• p = A frequency
– Compare A and a freq. over time
H-W Equilibrium
• No evolution is occurring
– No mutations, selection, gene flow, genetic drift
• Allele frequencies will not change
H-W Evolution
• Equilibrium requirements are rarely met,
so evolution is usually occurring
somewhere
– Mutation, selection, etc.
• Allele frequency is changing
WRAP UP
1. Write down the Hardy-Weinberg
equation.
2. Describe how Hardy-Weinberg
equilibrium is different than evolution.
WARM UP
1. Calculate the R and r frequency for the
handedness trait in the human
population, which is about 8% left-handed
(the recessive trait).
WRAP UP
• How do the numbers generated in the
Hardy-Weinberg equation show evolution?