The disorder is characterized by bruising, fatigue, anemia, low blood platelet count and enlargement of the liver and spleen, and is caused by a hereditary deficiency of the enzyme glucocerebrosidase (also known as glucosylceramidase), which acts on glucocerebroside.

When the enzyme is defective, glucocerebroside accumulates, particularly in white blood cells and especially in macrophages (mononuclear leukocytes, which is often a target for intracellular parasites).

Manifestations may include enlarged spleen and liver, liver malfunction, skeletal disorders or bone lesions that may be painful, severe neurological complications, swelling of lymph nodes and (occasionally) adjacent joints, distended abdomen, a brownish tint to the skin, anemia, low blood platelet count, and yellow fatty deposits on the white of the eye (sclera).

The disease is caused by a recessive mutation in the GBA gene located on chromosome 1 and affects both males and females.

[10] The disease is caused by a defect in the housekeeping gene for lysosomal glucocerebrosidase (also known as beta-glucosidase, EC 3.2.1.45, PDB: 1OGS​) on the first chromosome (1q22).

However, sphingolipids are known to participate in inflammation and apoptosis, and markers of macrophage activation are elevated in people with Gaucher disease.

These markers include angiotensin-converting enzyme, cathepsin S, chitotriosidase, and CCL18 in the blood plasma; and tumor necrosis factor alpha in splenic Gaucher cells (engorged macrophages).

[citation needed] A diagnosis can also be implied by biochemical abnormalities such as high alkaline phosphatase, angiotensin-converting enzyme, and immunoglobulin levels, or by cell analysis showing "crinkled paper" cytoplasm and glycolipid-laden macrophages.

[citation needed] Some lysosomal enzymes are elevated, including tartrate-resistant acid phosphatase, hexosaminidase, and a human chitinase, chitotriosidase.

Symptoms include an enlarged liver and spleen, extensive and progressive brain damage, eye movement disorders, spasticity, seizures, limb rigidity, and a poor ability to suck and swallow.

GD type III (chronic neuropathic) can begin at any time in childhood or even in adulthood and occurs in about 1 in 100,000 live births.

It is characterized by slowly progressive, but milder neurologic symptoms compared to the acute or type II version.

[28] For those with type-I and most type-III, enzyme replacement treatment with intravenous recombinant glucocerebrosidase can decrease liver and spleen size, reduce skeletal abnormalities, and reverse other manifestations.

[citation needed] The first drug for Gaucher's was alglucerase (Ceredase), which was a version of glucocerebrosidase that was harvested from human placental tissue and then modified with enzymes.

[30] It was approved by the FDA in 1991[31] and has been withdrawn from the market[32][33] due to the approval of similar drugs made with recombinant DNA technology instead of being harvested from tissue; drugs made recombinantly are preferable since there is no concern about diseases being transmitted from the tissue used in harvesting, there are fewer risks of variations in enzyme structure from batch to batch, and they are less expensive to manufacture.

[30] Available recombinant glucocerebrosidases are:[16] Miglustat is a small molecule, oral medication that was first approved for Gaucher's disease in Europe in 2002.