Hello. I am having trouble getting a grasp around Hardy-Weinberg Allele Frequencies. I understand that p +q = 1 and that p= freq. of dominant allele whereas q= freq. of recessive allele. I understand that the next part was derived by squaring the equation above: p2+2pq + q2=1 However, I do not understand how p2, 2pq, and q2 correspond to genotype frequencies. I created a scenario to test the equations and to better my understanding, but I don't know where I messed up: I took a population of seven individuals & imagined we are examining eye color. For the sake of simplicity there are only two possible alleles for eye color, brown (B) and green(g). Brown is dominant over green. There must be a total of 14 alleles then (b/c there are 7 individuals) and I assigned brown to 6 alleles and green to 8 alleles. In this scenario, therefore, p= 6/14 and q= 8/14 Now, according to the H-W, by squaring p, I should get the freq. of the homozygous dominant genotype. p2= 0.1837 However, I could have the following genotypes, which would give me a different freq. of BB. I could have: Bg gg Bg gg Bg BB Bg These combinations are consistent with the starting numbers 6 Bs and 8 gs. In this case, only 1 out of 7 genotypes is BB, giving a freq. of 0.1429, not 0.1837. I know have messed up in logic somewhere and am missing an important piece of understanding. Any pointers would be greatly appreciated.