Assume a biallelic locus in a diploid population has the genotype frequencies: A1A1 = 0.59; A1A2 = 0.16; and A2A2 = 0.25. What is the observed allele frequency (p) of the A1 allele?

0.67

Explanation:

Given

A1A1 = 0.59;

A1A2 = 0.16;

A2A2 = 0.25

p = Frequency of (A1)

q = freq (A2)

p = freq (A1A1) + (1/2) freq (A1A2)

= 0.59 + (1/2) (0.16) = 0.67.

0.67 is the observed allele frequency (p) of the A1 allele.

q = freq (A2A2) + (1/2) freq (A1A2)

or directly

q = 1-p = 0.33