Key Terms Books on Galactosemia Overview Galactosemia is an inherited disease where the transformation of galactose to glucose is blocked, allowing galactose to increase to toxic levels in the body. If Galactosemia is untreated, high levels of galactose cause vomiting, diarrhea, lethargy, low blood sugar, brain damage, jaundice, liver enlargement, cataracts, susceptibility to infection and death. Description Galactosemia is a rare but potentially tragic disease that kills very young babies. However, thanks to an understanding of the root of the problem, infant death from Galactosemia can be prevented by giving simple tests to newborns, Galactosemia is an inborn error of metabolism. A metabolic pathway is a series of reactions where the product of each step in the series is the starting material for the next step.
Defective genes cause inborn errors of metabolism.
A separate gene encodes each of these three enzymes. If any of these enzymes fail to function, galactose build-up and Galactosemia result. Thus, there are 3 types of Galactosemia with a different gene responsible for each. Each of the forms of Galactosemia is inherited as a recessive trait, which means that Galactosemia is only present in individuals with two defective copies of one of the three genes. This also means that carriers, with one copy of a defective recessive gene will not be aware they are carrying a defective gene.