Detection of inborn errors of metabolism. IV. Galactokinase deficiency.

Galactokinase deficient fibroblasts are not distinguishable from galactosemic fibroblasts by a test suggested earlier by Hill & Puck (1973). They can be so distinguished by the test described here, since they are unable to incorporate radioactive galactose into TCA-insoluble material under normal conditions of incubation while both galactosemic and normal cells incorporate considerable amounts. The importance of this is discussed in relationship to antenatal screening.