What does the q represent in hardy-weinberg equation?

Answer 1

It depends on what you make p equal to. P is usually the frequency of the dominant allele, which makes q the frequency of the recessive allele, but they can be switched. As long as p is one frequency and q is the other, the formula will work.

So if you have the dominant allele frequency (A) =.6 then the recessive allele frequency (a) =.4, because p+q=1

When you plug the frequencies into the hardy-weinberg equation

p^2 +2(p)(q) + (q)^2 = 1

then you have (0.6)^2 + 2(0.4)(0.6) + (0.4)^2 = 1

(0.6)^2 = 0.36 which is the frequency of dominant homozygotes

2(0.4)(0.6)=0.48 which is the frequency of heterozygotes

(0.)^2 = 0.16 which is the frequency of recessive homozygotes

If you have a population of 100 people, these frequencies would mean that:

36 people would be AA

48 people would be Aa

16 people would be aa

Which would mean that 36+48=84 people would exhibit the dominant trait and 16 people would show the recessive trait.