Phenylketonuria (PKU) is a human metabolic disease due to a single recessive gene

Phenylketonuria (PKU) is a human metabolic disease due to a single recessive gene. Homozygotes can be detected a few days after birth, and selective elimination before then will be assume to be negligible. Tests of babies born in Birmingham, UK, over a 3 year period detected 25 cases in 60,000 babies. What are the gene and genotype frequencies for PKU in this population?