Image:Lactose Haworth.Lactose File:Beta-D-Glucopyranose.Glucose File:Beta-D-Galactopyranose.Galactose Lactose in food (such as dairy products) is broken down by the enzyme lactase into glucose and galactose. In individuals with<unk> , the enzymes needed for further metabolism of galactose (Galactokinase and galactose-1-phosphate uridyltransferase) are severely diminished or missing entirely, leading to toxic levels of galactose or galactose 1-phosphate (depending on which enzyme is missing) in various tissues as in the case of classic<unk> , resulting in hepatomegaly (an enlarged liver), cirrhosis, kidney failure, cataracts, vomiting, seizure, low blood sugar (hypoglycemia), lethargy, brain damage, and ovarian failure. Without treatment, mortality in infants with<unk>  is about 75%.<unk>  is inherited in an autosomal recessive manner, meaning a child must inherit one defective gene from each parent to show the disease. Heterozygotes are carriers, because they inherit one normal gene and one defective gene. Carriers show no symptoms of<unk> .
Galactosemia
Pentosuria
Orotic aciduria
Glycosuria
D-Glyceric acidemia
Isovaleric acidemia
Hawkinsinuria
Sialuria