Sign in →

Test ID: GSDP Glycogen Storage Disease Panel by Next-Generation Sequencing

Useful For

Follow up of abnormal biochemical results consistent with glycogen storage disease

 

Identifying mutations within genes known to be associated with glycogen storage disease, allowing for predictive testing of at-risk family members

Reflex Tests

Test ID Reporting Name Available Separately Always Performed
CULFB Fibroblast Culture for Genetic Test Yes No
CULAF Amniotic Fluid Culture/Genetic Test Yes No
MATCC Maternal Cell Contamination, B Yes No

Testing Algorithm

See clinical information for recommended first-tier biochemical testing.

 

If skin biopsy is received, fibroblast culture will be added and charged separately.

 

For prenatal specimens only: If amniotic fluid (nonconfluent cultured cells) is received, amniotic fluid culture/genetic test will be added and charged separately. If chorionic villus specimen (nonconfluent cultured cells) is received, fibroblast culture for genetic test will be added and charged separately. For any prenatal specimen that is received, maternal cell contamination studies will be added.

Method Name

Custom Sequence Capture and Targeted Next Generation Sequencing followed by Polymerase Chain Reaction (PCR) and Sanger Sequencing

Reporting Name

Glycogen Storage Disease Panel

Specimen Type

Varies


Advisory Information


Due to the complexity of prenatal testing, consultation with the laboratory is required for all prenatal testing.



Additional Testing Requirements


All prenatal specimens must be accompanied by a maternal blood specimen.

-Order MATCC / Maternal Cell Contamination, Molecular Analysis on the maternal specimen.



Shipping Instructions


Specimen preferred to arrive within 96 hours of collection.

 

Prenatal specimens can be sent Monday through Thursday and must be received by 5 p.m. CST on Friday in order to be processed appropriately.



Specimen Required


Patient Preparation: A previous bone marrow transplant from an allogenic donor will interfere with testing. Call Mayo Medical Laboratories for instructions for testing patients who have received a bone marrow transplant.

 

Submit only 1 of the following specimens:

 

Specimen Type: Whole blood

Container/Tube:

Preferred: Lavender top (EDTA) or yellow top (ACD)

Acceptable: Any anticoagulant

Specimen Volume: 3 mL

Collection Instructions:

1. Invert several times to mix blood.

2. Send specimen in original tube.

Specimen Stability Information: Ambient (preferred)/Refrigerated

 

Specimen Type: Cultured fibroblasts

Container/Tube: T-75 or T-25 flask

Specimen Volume: 1 full T-75 or 2 full T-25 flasks

Specimen Stability Information: Ambient (preferred)/Refrigerated <24 hours

 

Prenatal Specimens

Specimen Type: Amniotic fluid

Container/Tube: Amniotic fluid container

Specimen Volume: 20 mL

Specimen Stability Information: Refrigerated (preferred)/Ambient

 

Specimen Type: Chorionic villi

Container/Tube: 15-mL tube containing 15 mL of transport media

Specimen Volume: 20 mg

Specimen Stability Information: Refrigerated

 

Acceptable

Specimen Type: Confluent cultured cells

Container/Tube: T-25 flask

Specimen Volume: 2 flasks

Collection Instructions: Submit confluent cultured cells from another laboratory.

Specimen Stability Information: Ambient (preferred)/Refrigerated

 

Specimen Type: Skin biopsy

Supplies: Fibroblast Biopsy Transport Media (T115)

Container/Tube: Sterile container with any standard cell culture media (eg, minimal essential media, RPMI 1640). The solution should be supplemented with 1% penicillin and streptomycin. Tubes can be supplied upon request; Eagle's minimum essential medium with 1% penicillin and streptomycin (T115).

Specimen Volume: 4-mm punch

Specimen Stability Information: Refrigerated (preferred)/Ambient

 

Specimen Type: Blood spot

Supplies: Card - Blood Spot Collection (Filter Paper) (T493)

Preferred: Collection card (Whatman Protein Saver 903 Paper)

Acceptable: Ahlstrom 226 filter paper, or Card-Blood Spot Collection (Filter Paper) (T493)

Specimen Volume: 3 to 5 Blood Spots on collection card

Collection Instructions:

1. An alternative blood collection option for a patient >1 year of age is finger stick.

2. Let blood dry on the filter paper at ambient temperature in a horizontal position for 3 hours.

3. Do not expose specimen to heat or direct sunlight.

4. Do not stack wet specimens.

5. Keep specimen dry

Specimen Stability Information: Ambient (preferred)/Refrigerated

Additional Information:

1. For collection instructions in Spanish, see Blood Spot Collection Card-Spanish Instructions (T777) in Special Instructions.

2. For collection instructions in Chinese, see Blood Spot Collection Card-Chinese Instructions (T800) in Special Instructions.


Specimen Minimum Volume

Blood: 1 mL
Blood Spots: 3, 3-mm diameter
Amniotic Fluid: 10 mL
Chorionic Villi: 5 mg

Specimen Stability Information

Specimen Type Temperature Time
Varies Ambient (preferred)
  Frozen 
  Refrigerated 

Clinical Information

Glycogen storage diseases (GSDs) are a group of inherited metabolic conditions caused by deficiency of enzymes responsible for glycogen metabolism, resulting in abnormal storage of glycogen in the liver and various muscles. There are over 15 different glycogen storage diseases which vary in symptoms and severity, dependent on the enzyme deficiency, although liver and muscle are most commonly affected.

 

Generally, they can be divided into 2 categories, those with hepatic involvement and those with neuromuscular involvement. Some GSDs result in single tissue disease, while others affect multiple organs. Clinical features may include hepatomegaly, hypoglycemia, muscle cramps, exercise intolerance, and progressive fatigue and weakness. Preliminary biochemical testing may be helpful in making a diagnosis. Recommended first-tier biochemical testing includes glucose monitoring, triglycerides, uric acid level, creatine kinase, liver function tests, and complete blood count.

 

This test involves sequencing of 26 genes related to various glycogen storage diseases. See table below for additional information.

 

Gene

Disease Name

OMIM ID

Inheritance

AGL

Glycogen storage disease type III

232400

AR

ALDOA

Glycogen storage disease XII

611881

AR

ENO3

Glycogen storage disease XIII

612932

AR

EPM2A

Lafora progressive myoclonus epilepsy

254780

AR

G6PC

Glycogen storage disease type Ia, mitochondrial

232200

AR

GAA

Pompe disease-glycogen storage disease type II

232300

AR

GBE1

Glycogen storage disease type IV-adult polyglucosan body disease

232500, 263570

AR

GYG1

Glycogen storage disease type XV

613507

AR

GYS1

Glycogen storage disease type 0-muscle

611556

AR

GYS2

Glycogen synthase 2 (glycogen storage disease 0, liver)

240600

AR 

LAMP2

Glycogen storage disease type IIb-Danon disease

300257

XLD

LDHA

Glycogen storage disease type XI- lactate dehydrogenase deficiency

612933

AR

NHLRC1

Lafora progressive myoclonus epilepsy

254780

AR

PFKM

Glycogen storage disease type VII

232800

AR

PGAM2

Glycogen storage disease type X-phosphoglycerate mutase deficiency

261670

AR

PGK1

Phosphoglycerate kinase deficiency

300653

XLR

PGM1

Phosphoglucomutase 1 (glycogen storage disease XIV)

614921

AR

PHKA1

Phosphorylase kinase, alpha 1 (muscle) (Glycogen storage disease, type IXD)

300559

XLR 

 

PHKA2

Glycogen storage disease type IXA

306000

XLR

PHKB

Glycogen storage disease, IXb

261750

AR

PHKG2

Glycogen storage disease type IXC

613027

AR

PRKAG2

Glycogen storage disease of the heart -Wolff-Parkinson-White syndrome

194200, 261740

AD

PYGL

Glycogen storage disease type VI

232700

AR

PYGM

Glycogen storage disease type V, McArdle disease

232600

AR

SLC2A2

Glycogen storage disease type 11, GLUT-2 deficiency, Fanconi Bickel syndrome

2227810

AR

SLC37A4

Glycogen storage disease type Ib and Ic

232220

AR

AR=autosomal recessive

AD=autosomal dominant

XLD=X-linked dominant

XLR=X-linked recessive

Reference Values

An interpretive report will be provided.

Interpretation

All detected alterations are evaluated according to American College of Medical Genetics and Genomics recommendations.(1) Variants are classified based on known, predicted, or possible pathogenicity and reported with interpretive comments detailing their potential or known significance.

 

Multiple in silico evaluation tools may be used to assist in the interpretation of these results. The accuracy of predictions made by in silico evaluation tools is highly dependent upon the data available for a given gene, and predictions made by these tools may change over time. Results from in silico evaluation tools should be interpreted with caution and professional clinical judgment.

Clinical Reference

1. Richards S, Aziz N, Bale S, et al: Standards and guidelines for the interpretation of sequence variants: a joint consensus recommendation of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology. Genet Med 2015 May;17(5):405-424

2. Chen YT, Kishani PS, Koeberl D: Glycogen Storage Disease. The Online Metabolic and Molecular Bases of Inherited Diseases. Edited by D Valle, B Vogelstein, KW Kinzler, et al.

3. Hicks J, Wartchow, E, Mierau G: Glycogen Storage Diseases: A Brief Review and Update on Clinical Features, Genetic Abnormalities, Pathologic Features, and Treatmen. Ultrastruct Pathol 2011;35(5):183-196

Day(s) and Time(s) Performed

Performed weekly, Varies

Analytic Time

4 weeks

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information

81250-G6PC

81403-NHLRC1

81404-EPM2A

81405-LAMP2

81406 x 4-GAA, PRKAG2, SLC37A4, PYGM

81479

81407-AGL

 

Fibroblast Culture for Genetic Test

88233-Tissue culture, skin or solid tissue biopsy (if appropriate)

88240-Cryopreservation (if appropriate)

 

Amniotic Fluid Culture/Genetic Test

88235-Tissue culture for amniotic fluid (if appropriate)

88240-Cryopreservation (if appropriate)

 

Maternal Cell Contamination, B

81265-Comparative analysis using Short Tandem Repeat (STR) markers; patient and comparative specimen (eg, pre-transplant recipient and donor germline testing, post-transplant non-hematopoietic recipient germline [eg, buccal swab or other germline tissue sample] and donor testing, twin zygosity testing or maternal cell contamination of fetal cells (if appropriate)

LOINC Code Information

Test ID Test Order Name Order LOINC Value
GSDP Glycogen Storage Disease Panel In Process

 

Result ID Test Result Name Result LOINC Value
41754 Result Summary 50397-9
41755 Result In Process
41756 Interpretation In Process
41757 Additional Information 48767-8
41758 Specimen 31208-2
41759 Source 31208-2
41760 Released By No LOINC Needed

Forms

1. New York Clients-Informed consent is required. Please document on the request form or electronic order that a copy is on file. An Informed Consent for Genetic Testing (T576) is available in Special Instructions.

2. Molecular Genetics Molecular Genetics: Biochemical Disorders Patient Information (T527) in Special Instructions

Mayo Medical Laboratories | Genetics and Pharmacogenomics Catalog Additional Information:

mml-inherited-molecular