Test Overview
Test Methodology

Enzyme Reaction Followed by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

Test Usage

The diagnosis of galactose-1-phosphate uridyltransferase deficiency, the most common cause of galactosemia.

Reference Range *

> or =24.5 nmol/h/mg of hemoglobin

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Limitations

This assay is not useful for monitoring dietary compliance. This assay will not detect galactokinase deficiency or uridine diphosphate galactose 4-epimerase deficiency.

Test Details
Days Set Up
Monday, Wednesday, Friday
Analytic Time

4 - 8 days

Soft Order Code
  • G-1-PU
  • GPUT
  • G-1-PU
  • GPUT
  • GALT (Galactose-1-Phosphate Uridyltransferase)
Reference Laboratory
Mayo GALT (8333)
Special Testing
Specimen Requirements
Collection Instructions

Collect blood in a lavender top tube. Refrigerate and send intact whole blood specimen; do not freeze. Green top (sodium heparin) or yellow top (ACD) tube also acceptable.

Alternate Specimen
Heparinized (green top) or ACD (yellow top) tubes are also acceptable. [3/02]
Normal Volume
5 mL EDTA whole blood
Minimum Volume
2 mL EDTA whole blood
Additional Information

Test sent to Mayo Clinic Laboratories.

CPT Code
Fee Code