Enzymes involved in phenylalanine metabolism in the human foetus and child

The activities of phenylalanine p-hydroxylase, tyrosine: alpha-ketoglutarate and phenylalanine: pyruvate aminotransferases, and aromatic alpha-ketoacid reductase have been measured in liver biopsies obtained from children with a series of disorders other than phenylketonuria and from human foetuses aged 8.5 to 24 weeks. The importance of such a study in relation to the management of infants with hyperphenylalaninaemia and pregnant phenylketonuric women is discussed