Uridine nucleotide sugars in erythrocytes of patients with galactokinase deficiency.

The levels of UDPglucose and UDPgalactose (UDPGal) have been measured in erythrocytes of seven patients with galactokinase deficiency. Normal levels of UDPGal were found in all patients with galactokinase deficiency (McKusick 23020). This is in contrast with reduced values of UDPGal found in patients with classical galactosaemia who have complete absence of galactose-1-phosphate uridyl transferase activity. It was demonstrated that patients with galactokinase deficiency had an incomplete enzyme block in erythrocytes by direct enzyme assay, by 14CO2 production from [1-14C]galactose, and by the appearance of labelled intermediates, notably galactose-1-phosphate and UDPhexose.