Plasma Lyso-GL1 Analysis
Related Gene(s): GBA
Gaucher disease is an autosomal recessive lysosomal storage disease caused by a deficiency of glucocerebrosidase (acid β-glucosidase). Accumulation of glucosylceremide (GL1) and glucosylsphinogosine (lyso-GL1) occurs in cells of the monocyte or macrophage lineage, including the spleen, liver, and bone marrow contributing to the pathogenicity of this disease.
Gaucher disease is seen in approximately 1 in 40,000 to 1 in 50,000 people worldwide, but is much more frequent in the Ashkenazi Jewish population (1 in 850 people). The signs and symptoms of this condition can vary widely among affected individuals, but are broadly divided into three major clinical types. Type 1 is non-neuronopathic and is the most common form of Gaucher disease. It is characterized by hepatosplenomegaly, anemia, thrombocytopenia, bone disease, and lung disease. Types 2 and 3 include neurologic involvement (neuronopathic), in addition to the skeletal and visceral abnormalities seen in type 1. Type 2 is the most severe form, with onset prior to 2 year of age, limited psychomotor development, and rapid neurodegeneration. Death occurs prior to 4 years of age. Type 3 has a severity that is intermediate between type 1 and type 2, with survival into the 3rd or 4th decade of life.
Plasma lyso-GL1 is found to be markedly elevated to approximately 200-fold in the plasma of symptomatic non-neuronopathic Gaucher patients and seems to correlate with other Gaucher cell markers, such as chitotriosidase and PARC/CCL18. Plasma lyso-GL1 can assist in the diagnosis of Gaucher disease and is useful in monitoring the disease progression and therapeutic efficacy.
Lyso-GL1 is extracted from plasma, fully separated from its isomer galactosylsphingosine, and analyzed by a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Plasma lyso-GL1 is indicated
- If there are any clinical signs and symptoms suggestive of Gaucher disease
- For infants with positive newborn screening findings for Gaucher disease
- For known Gaucher patients on enzyme replacement or substrate reduction therapy
- For monitoring for disease progression in presymptomatic Gaucher patients
- Blood: 1-2 mL in EDTA tube (lavender top) or sodium heparin tube (green top). Minimum of 0.5 mL is required
- Plasma: 0.5-1 mL. Minimum of 100 μL is required
- Separate plasma immediately and ship frozen plasma on dry ice
- Ship and store frozen until analysis
- 5 days