Neonatal screening for dihydropteridine reductase deficiency

Abstract

Dihydropteridine reductase (DHPR, EC 1.6.99.7) deficiency (McKusick 26163) is a rare cause of hyperphenylalaninaemia and neurological disease. It is important to distinguish it from the more prevalent cause of these, phenylalanine hydroxylase deficiency (McKusick 26160), as the treatment in the two cases is different (for review see Danks et al., 1978; Dhondt, 1984). DHPR activity can be readily measured in dried blood spots on Guthrie cards (Arai et al., 1982; Leeming et al., 1984). We have used this technique to screen for DHPR deficiency in control and hyperphenylalaninaemic neonates.