Galactosemia
Inability of conversion of galactose to glucose results in the accumulation of galactose in the blood - known as galactosemia. The biochemical defect usually found in galactosemia is the deficiency of the enzyme galactose-1-phosphate uridyl transferuse. Initially, galactose accumulates in the tissues, then in the blood. The major organ damaged by galactose accumulation is liver. Galactose is reduced to the corresponding alcohol called galactitol in the eye which causes cataract.