Gaucher Disease is a rare, inherited, potentially fatal disorder. Deficiency of the enzyme -glucocerebrosidase leads to an accumulation of glucosylceramide in storage compartments (lysosomes) of certain cells in the body.
It is the most common type of a group of diseases known as Lysosomal storage diseases. Lysosomes are cell compartments in which substances are broken down by specific enzymes. This is analogous to a machine breakdown at an assembly plant causing a huge pileup of unfinished products.
Deficiency of this enzyme causes the lysosomes to become congested with glucosylceramide. These congested lysosomes buildup in the liver, spleen, bones, and bone marrow. This, in turn, leads to decreased production of red blood cells (anemia), and thinning of the bones (osteopenia).
It is an autosomal recessive disease. This means that an affected child would inherit two abnormal copies of the enzyme, one from the mother and one from the father. The parents are known as "carriers" since they do not manifest the disease, but silently harbor one abnormal copy of the gene.
There are three forms of Gaucher Disease, Types 1, 2, and 3, that are recognized. They are classified by age of onset (infantile, juvenile, adult) and the presence or absence of neurological involvement.
- Type 1 disease is the most commonly seen form affecting both children and adults. It is most prevalent in the Ashkenazi Jewish population, affecting anywhere from 1 out of 500-1,000 births. Type 1 disease is characterized by the lack of neurologic involvement.
- Type 2 disease usually presents in infancy with severe neurologic involvement. This form, in addition to spleen and bone marrow damage, causes seizures and damage to the central nervous system (CNS). Central nervous system symptoms include: abnormal gait (ataxia), paralysis of eye muscles (ophthalmoplegia), and dementia.
- Type 3 disease typically has mild neurologic involvement and runs a slower, more favorable course. The incidence of Types 2 and 3 diseases is 1 out of every 50,000 to 100,000 births. The juvenile form can begin in childhood, often the teens, and cause spleen, bone marrow, and neurologic damage.
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