The most serious form of galactosemia in humans is due to deficiency of :
A. GalactokinaseB. Galactose-1-phosphate uridyltransferase
C. Galactosidase
D. UDP-galactoseepimerase
E. Phospho-fructokinase
Answer. B. Galactose-1-phosphate
uridyltransferase
Uridyltransferase
is defective in classical galactosemia. In nonclassical galactosemia, galactokinase
is defective. Galactokinase deficiency is not as severe as uridyltransferase
deficiency because of the lack of buildup of charged intracellular metabolites.
