A modified method for the estimation of galactose-1-phosphate.

The measurement of galactose-1-phosphate has been advocated for monitoring galactosaemia. A radioenzymatic method is described in which red-cell haemolysates are incubated with radiolabelled uridine diphospho-glucose and exogenous galactose-1-phosphate uridyl transferase. Labelled glucose-1-phosphate is formed in proportion to the amount of galactose-1-phosphate present and is separated from the labelled uridine diphospho-glucose by affinity chromatography. The method is reproducible and has a low limit of detection. This allows it to be carried out on 100 microL of packed red cells.