GALT (Galactose-1-phosphate Uridylyltransferase) Gene Mutation Analysis, Blood
A blood-based genetic test that looks for changes in the GALT gene, which can cause the inherited metabolic condition galactosemia.
["Identifies GALT gene variants that may cause galactosemia or indicate carrier status."]
Key facts at a glance
- LOINC
- 42318-6
- Short code
- GALT gene Mut Anl Bld/T
- Synonyms
- GALT gene Mut Anl Bld/T
- Category
- liver
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 7
- Ref high
- 56
- Critical range
- — – 500 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- molgen
- CPT
- 84484
- SNOMED
- 302773008
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
What is this test?
This test examines DNA from a blood sample for variants in the GALT gene. GALT provides instructions for making an enzyme called galactose-1-phosphate uridylyltransferase, which helps the body process galactose, a type of sugar found in milk and some other foods.
Why might I need this test?
This test may be ordered after a newborn screening result suggests galactosemia, when an infant or child has symptoms that could be related to the condition, or when a family history or another genetic test suggests a GALT-related disorder. It may also be used to assess whether a relative is a carrier.
How is the test performed?
A blood sample is collected, and its DNA is analyzed in a laboratory to look for selected changes in the GALT gene. The exact testing approach and the types of variants that can be detected depend on the laboratory and the reason the test was ordered.
How do I prepare for the test?
No special preparation is usually required for a routine blood draw, and you generally do not need to fast. Follow any instructions provided by the testing laboratory or your healthcare professional, especially if the test is part of a broader genetic evaluation.
Reference range
Adult males: 7-56 U/L; Adult females: 7-43 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
GALT genetic test
Frequently asked questions
Does this test measure GALT enzyme activity?
What is galactosemia?
Can this test determine if I am a carrier?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy