The Genetic Defect in Galactosemia

Abstract
GALACTOSE-1-PHOSPHATE uridylytransferase (E.C. 2.7.7.12—subsequently referred to as "transferase") is the enzyme whose function is markedly, if not totally, deficient in the commonly recognized form of galactosemia — an inborn error of metabolism that was described as a clinical entity in 1908 and defined as resulting from a specific enzyme defect in 1956.1 Of all the enzymes involved in human genetic disease, this one has been particularly responsive to the combined attacks of biochemistry and genetics. Enough has been learned about this enzyme to enable a description of its mechanism of action in molecular terms, as well as a look at . . .