Geneticsm question??

Question

64% of animals in a population are of the genotype AA.Given that there are only 2 allels A and a at this locus what is the percentage of aa and Aa Animlas in the population??

i have no idea how to even start...

Answer 1

The genotype frequency for AA =.64

If you want to assume Hardy-Weinberg equilibrium, this means that p^2 =.64, so p=.8.  

p+q=1, so q must =.2

Hardy-Weinberg equilibrium:

p^2 + 2pq + q^2

.64 + (2*.8*.2) + .2^2

=.64 + .32 + .04

So, you have 64%AA, 32%Aa, and 4%aa.