Galactosemia

What is galactosemia?

Galactosemia means “galactose in the blood”. Babies with this metabolic condition are not able to metabolize a certain type of sugar (galactose) found primarily in breast milk, cow’s milk, and dairy products. When galactose can’t be broken down and digested, it builds up in the tissues and blood in large amounts. Its byproducts also build up in large amounts.

Galactosemia is a rare genetic disorder where galactose (a by-product of lactose digestion) fails to convert to glucose.

Lactose is one of the main carbohydrate components present in milk. In the infant intestine, this lactose is broken down into glucose and galactose, which are then used as a source of energy.

In healthy babies, galactose is further metabolized and converted to glucose via a series of enzymatic reactions, one of which involves the enzyme galactose-1-phosphate uridyl transferase (GALT)..

In galactosemia, this enzyme is either defective or missing. When this happens, an infant is unable to convert the galactose into glucose, which causes galactose to accumulate in the blood. This can lead to serious problems such as liver enlargement, kidney failure, brain damage and cataracts. Left untreated, this condition kills up to 75% of sufferers.

Types of galactosemia?

There are three forms of the disease:

· Galactose-1 phosphate uridyl transferase deficiency (classic galactosemia, the most common and most severe form)

· Deficiency of galactose kinase

· Deficiency of galactose-6-phosphate epimerase