PKU — Some Skepticism

Abstract

A simple syllogism has governed thinking and publicity about phenylketonuria (PKU) and a large number of other diseases of metabolism associated with mental retardation. The patient has too much of some normal intermediate in his body fluids, owing to an enzyme defect, and this has led in some way to his mental retardation. The partial or complete removal of the offending material from the diet will prevent this brain damage.In phenylketonuria the high-water mark of the movement was reached at an international meeting¹ in 1967 when serious investigators from at least two centers reported that the eventual mean IQ . . .