Molecular basis of disorders of human galactose metabolism: past, present, and future.
Molecular cloning and characterization of all three human galactose-metabolic genes have led to the identification of a number of mutations which result in three forms of galactosemia which are caused by kinase (GALK), transferase (GALT), or epimerase (GALE) deficiency. We review here recent developments in the molecular characterization of all three disorders of human galactose metabolism. Recent progress in the biochemical and/or structural analyses of the GALT and GALE proteins has complemented human mutational studies. Interestingly, genotype/phenotype correlations have been modest as in some other Mendelian disorders. We discuss possible reasons for this apparent paradox. Finally, we note the panethnic nature of galactosemia and suggest a hypothesis for it.
Novelli
G
G
Dipartimento di Biopatologia e Diagnostica per Immagini, Università di Roma Tor Vergata, Rome, 00133, Italy.
Reichardt
J K
JK
D005686:Galactokinase / Q000172:deficiency / Q000235:genetics; D005690:Galactose / Q000378:metabolism*; D005693:Galactosemias / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D009154:Mutation; D014534:UDPglucose 4-Epimerase / Q000172:deficiency / Q000235:genetics; D005694:UTP-Hexose-1-Phosphate Uridylyltransferase / Q000172:deficiency / Q000235:genetics
D005686:Galactokinase; D005694:UTP-Hexose-1-Phosphate Uridylyltransferase; D014534:UDPglucose 4-Epimerase; D005690:Galactose