Order Code LABGOR, BGA Beta-Galactosidase, Leukocytes
Additional Codes
Mayo Test Code: BGA
Reporting Name
Beta-Galactosidase, LeukocytesUseful For
Aiding in the diagnosis of GM1 gangliosidosis, Morquio B disease, and galactosialidosis
This test is not suitable for carrier detection.
Performing Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
Whole Blood ACDShipping Instructions
For optimal isolation of leukocytes, it is recommended the specimen arrive refrigerated within 6 days of collection to be stabilized. Collect specimen Monday through Thursday only and not the day before a holiday. Specimen should be collected and packaged as close to shipping time as possible.
Necessary Information
Provide a reason for referral with each specimen.
Specimen Required
Container/Tube:
Preferred: Yellow top (ACD solution B)
Acceptable: Yellow top (ACD solution A)
Specimen Volume: 6 mL
Collection Instructions: Send specimen in original tube. Do not aliquot.
Specimen Minimum Volume
5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Whole Blood ACD | Refrigerated (preferred) | 6 days | YELLOW TOP/ACD |
Ambient | 6 days | YELLOW TOP/ACD |
Special Instructions
Reference Values
≥1.56 nmol/min/mg
Day(s) Performed
Preanalytical processing: Monday through Sunday
Assay performed: Tuesday
CPT Code Information
82657
Genetics Test Information
Beta-galactosidase enzyme is deficient in the following conditions: GM1 gangliosidosis, Morquio syndrome B, and galactosialidosis.
Careful review of clinical findings will help distinguish between GM1 gangliosidosis and Morquio syndrome type B.
A diagnosis of galactosialidosis must be additionally demonstrated by a deficiency of neuraminidase.
Method Description
The deficiency of beta-galactosidase is demonstrable using the artificial substrate 4-methylumbelliferyl-beta-D-galactopyranoside. The enzyme hydrolyzes the artificial substrate to produce 4-methylumbelliferone, which is measured fluorometrically.(Ho MW, O'Brien JS: Differential effect of chloride ions on galactosidase isoenzymes: a method for separate assay. Clin Chim Acta. 1971 May;32[3]:443-450; Gehler J, Cantz M, Tolksdorf M, Spranger J, Gilbert E, Drube H: Mucopolysaccharidosis. VII. Beta-glucuronidase deficiency. Humangenetik. 1974 July 15;23[2]:149-158. doi: 10.1007/BF00282212; Cowan T, Pasquali M: Laboratory Investigations of Inborn Errors of Metabolism. In: Sarafoglou K, Hoffman GF, Roth KS, eds. Pediatric Endocrinology and Inborn Errors of Metabolism. 2nd ed. McGraw-Hill; 2017:1139-1158)
Reject Due To
Gross hemolysis | Reject |
Method Name
Fluorometric
Forms
1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available:
-Informed Consent for Genetic Testing (T576)
-Informed Consent for Genetic Testing-Spanish (T826)
2. Biochemical Genetics Patient Information (T602)
3. If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.
Testing Algorithm
See Lysosomal Storage Disorders Diagnostic Algorithm, Part 1