Gaucher Disease: GBA Sequencing

Turnaround Time

3 weeks

CPT Code(s)

81479

Cost

$1,000

Genes

• Gaucher Disease

Gaucher disease, a lysosomal storage disorder, can present with a wide spectrum of severity ranging from a perinatal lethal phenotype to asymptomatic. There are three primary types with two additional subtypes, all categorized by differences in the clinical presentation of the patient. Hepatosplenomegaly, pulmonary disease, and cytopenia are also common for most types of Gaucher disease. Patients with Gaucher disease type 1 have varying degrees and types of bone disease as the primary feature, but do not have any central nervous system involvement. Gaucher disease types 2 and 3 present with primary neurologic disease. Type 2 and 3 are distinguished based on age of onset and disease progression. Patients with type 2 typically have an earlier onset before age 2, rapid disease progression, and early death. Type 3 is characterized by a slower disease course with patients living into adulthood. Neurologic findings for types 2 & 3 include bulbar signs, pyramidal signs, oculomotor apraxia, seizures, as well as dementia and ataxia in later disease stages. The perinatal lethal form may present as nonimmune hydrops fetalis or with pyramidal neurologic signs and ichthyosiform skin changes. The cardiovascular form is characterized by primarily by calcification of mitral and aortic values with other minor findings.

Biomarker analysis of chitotriosidase can be used to monitor disease progression for affected individuals including those receiving enzyme replacement therapy.

Sanger Sequencing

The preferred sample type is 3-5 ml of peripheral blood collected in an EDTA (purple top) tube. Extracted DNA, dried blood spots, and saliva are also accepted for this test. Saliva samples must be submitted in an approved saliva kit. Contact the lab to receive a saliva kit or to have one sent to your patient.

The specimen should be kept at room temperature and delivered via overnight shipping. If shipment is delayed by one or two days, the specimen should be refrigerated and shipped at room temperature. Do not freeze the specimen. Samples collected on Friday can be safely designated for Monday delivery.

Prenatal diagnosis is available if the familial mutations are known. Additional fees for cell culture and maternal cell contamination may apply. Maternal cell contamination studies are required for all prenatal molecular tests. Contact the laboratory prior to sending a prenatal specimen.