Question

In humans, there is a phenotype for curly hair and a phenotype for straight hair. The homozygous dominant genotype CC is for curly hair, and the homozygous recessive genotype cc is for straight hair. Heterozygous Cc is a phenotype for wavy hair.

In a hypothetical population, 36% of people are born with straight hair (cc). What percentage of this population will have wavy hair?

Answer 1

Using the Hardy Weinberg equation p^2+2pq+q^2=1 and p+q=1
q^2 = .36 (the proportion of homozygous recessive)
q = .6
p = .4
2pq = .48
48% of the population will have wavy hair.