Gaucher Disease (GD) is an inherited condition that can damage many different parts of the body. Damage occurs when a type of fat — glucocerebroside — builds up in certain organs in the body. Normally, we have an enzyme—glucocerebrosidase — that eliminates this bad fat. People with GD do not make enough of this enzyme. GD typically causes a large liver and spleen, anemia, low platelet count, lung disease, and sometimes brain disease.
There are three basic types of GD. Type 1 (GD1) causes nearly all of the symptoms listed above, except for brain disease. GD2 and GD3 cause all the listed symptoms, including effects on the brain. GD2 is the most severe, with symptoms beginning before age 2. In GD3, the symptoms may begin before age 2, but are more mild and slower to worsen. More recently, experts on Gaucher disease have realized that some patients do not exactly fit into these categories. Symptoms of patients with GD2 and GD3 can vary.
GD is rare; it affects about 1 person in 100,000. In certain ethnic groups, such as Ashkenazi Jews, GD1 can affect up to 1 in 1,000 people. About 90-95% of cases are GD1, making it the most common form.
All three types of GD are caused by a change, or mutation, in a gene called GBA, which is responsible for making the glucocerebrosidase enzyme. Gaucher disease is an autosomal recessive genetic disorder. This means that the person with the disease must inherit two mutations in the gene, one from their mother and one from their father. Without any normal GBA gene, the person cannot make sufficient amounts of glucocerebrosidase to prevent the abnormal fatty accumulation.
If both parents carry a genetic mutation for GD, each of their children has a 25% chance of inheriting GD. Usually the parents do not know that they carry the gene. Some ethnic groups — such as Ashkenazi Jews — often get tested to determine if they are carriers before having children.