Test ID G6PDZ Glucose-6-Phosphate Dehydrogenase (G6PD) Full Gene Sequencing, Varies
Ordering Guidance
For initial or time-sensitive screening for glucose-6-phosphate dehydrogenase deficiency, order G6PD1 / Glucose 6-Phosphate Dehydrogenase Enzyme Activity, Blood.
Necessary Information
Include physician name and phone number with the specimen.
Specimen Required
Submit only 1 of the following specimens:
Specimen Type: Whole blood
Container/Tube:
Preferred: Lavender top (EDTA) or yellow top (ACD)
Specimen Volume: 3 mL
Collection Instructions:
1. Invert several times to mix blood.
2. Send whole blood specimen in original tube. Do not aliquot.
Specimen Stability Information: Ambient (preferred) 9 days/Refrigerated 30 days
Specimen Type: Saliva
Patient Preparation: Patient should not eat, drink, smoke, or chew gum 30 minutes prior to collection.
Supplies: Saliva Swab Collection Kit (T786)
Specimen Volume: 1 Swab
Collection Instructions: Collect and send specimen per kit instructions.
Specimen Stability Information: Ambient 30 days
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. If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:
-Therapeutics Test Request (T831)
Useful For
Genetic test for individuals at high risk for glucose-6-phosphate dehydrogenase (G6PD) deficiency
Aiding in the diagnosis of G6PD deficiency
Determining G6PD deficiency status in individuals with inconclusive or unexpected phenotyping results
Differentiation of heterozygotes with skewed X-inactivation from homozygotes and compound heterozygotes
Definitive diagnosis of carrier status
Evaluation of neonates with unexplained jaundice
Identifying individuals at risk of drug-induced acute hemolytic anemia related to G6PD deficiency
Genetics Test Information
This test is for molecular sequencing of the G6PD gene and does not assess glucose-6-phosphate dehydrogenase (G6PD) enzyme activity. Enzymatic testing may be suggested as follow-up to this assay. For G6PD enzyme testing order G6PD1 / Glucose 6-Phosphate Dehydrogenase Enzyme Activity, Blood.
G6PD deficiency is a common X-linked condition, estimated to affect up to 500 million people worldwide. Both male and female patients may be impacted due to how common G6PD deficiency is in the population.
Acute hemolytic anemia (AHA) can be triggered in individuals with G6PD deficiency by fava beans, several types of medications (including rasburicase, dapsone-containing combinations of antimalarial drugs, and methylene blue), and infection. Less commonly, chronic congenital nonspherocytic hemolytic anemia (CNSHA) may occur in severe forms of G6PD deficiency.
US Food and Drug Administration labeling and Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines recommend that G6PD testing be undertaken in high-risk populations before prescribing drugs known to cause AHA. Knowing a patient's genotype is generally sufficient to avoid contraindicated drugs, but follow-up with the phenotyping (enzyme) assay may be necessary to clarify results in some cases.
This test involves full gene sequencing of all exons and exon/intron boundaries of the G6PD gene. A comprehensive interpretation will be provided including congenital and pharmacogenomic implications of results. Testing should be considered before prescribing medication associated with hemolysis in individuals with G6PD deficiency.
Special Instructions
Method Name
Polymerase Chain Reaction (PCR) followed by DNA Sequence Analysis
Reporting Name
G6PD Full Gene Sequencing, VSpecimen Type
VariesSpecimen Minimum Volume
Blood: 0.45 mL
Saliva: See Specimen Required
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Varies |
Reference Values
An interpretive report will be provided.
Day(s) Performed
Monday, Wednesday
Report Available
3 to 7 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
81249
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
G6PDZ | G6PD Full Gene Sequencing, V | 94231-8 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
618837 | G6PD Phenotype | 47998-0 |
618838 | Result Details | 82939-0 |
618839 | Interpretation | 69047-9 |
618840 | Additional Information | 48767-8 |
618841 | Method | 85069-3 |
618842 | Disclaimer | 62364-5 |
618843 | Reviewed By | 18771-6 |
NY State Approved
YesTesting Algorithm
The following are available:
-Glucose-6-Phosphate Dehydrogenase (G6PD) Deficiency Diagnostic Algorithm
-Glucose-6-Phosphate Dehydrogenase (G6PD) Genotyping Interpretive Algorithm