About one child in 2,500 is born with phenylketonuria ( an inability to metabolize the amino acid phenylalanine). This is known to be a recessive autosomal trait.
a) If the population in Hardy-Weinberg equilibrium for this trait, what is the frequency of the phenylketonuria allele?
b) What proportion of the population are carriers of the phenylketonuria allele (that is, what proportion are heterozygous)?