Task

Phenylketonuria is inherited as an autosomal recessive trait (a — disease allele). In a city of 500,000 people the disease occurs in one of every 10,000 newborns. Treat the population as ideal (random mating, large, no migration or selection). 1) State the Hardy–Weinberg law, its conditions and formulas, and describe the method of solution. 2) Find the frequencies of the recessive and dominant alleles. 3) Calculate the genotype frequencies (%) and the number of people of each genotype in the city. 4) Calculate the probability that a phenotypically healthy, randomly chosen couple has a child with phenylketonuria. For each part, write out the law or method used (cross scheme, formulas, reasoning) and all calculations step by step.