Effect of genotype on changes in intelligence quotient after dietary relaxation in phenylketonuria and hyperphenylalaninaemia.

Background: Associations between genotype and intellectual outcome in patients with phenylketonuria are complicated because intelligence is influenced by many variables, including environmental factors and other genetic determinants. Intellectual changes with age, both on and after relaxation of diet, vary within the patient population. This study aims to determine whether a significant association exists between genotype and change in intelligence after relaxation of diet.

Fractures and phenylketonuria.

Parent or self-reported history of fractures in a group of patients aged from 0.3 to 33.6 years on dietary treatment for phenylketonuria was studied by means of a questionnaire.

Radiological assessment of the hand and wrist in phenylketonuria and hyperphenylalaninaemia.

A radiograph of the left hand and wrist was taken in 141 children and young adults with phenylketonuria and hyperphenylalaninaemia. Ten (7.1%) had a bony abnormality and, of these, six (4.