Test Code SMNDX |Beaker: LAB1383 Spinal Muscular Atrophy Diagnostic Assay, Deletion/Duplication Analysis, Varies
Additional Codes
Epic EAP: LAB1383
Epic Description: SPINAL MUSCULAR ATROPHY, DNA
For Carrier testing, use order LAB8467 (SMNCS)
Additional Testing Requirements
All prenatal specimens must be accompanied by a maternal blood specimen; order MATCC / Maternal Cell Contamination, Molecular Analysis, Varies on the maternal specimen.
Shipping Instructions
Specimen preferred to arrive within 96 hours of collection.
Specimen Required
Patient Preparation: A previous bone marrow transplant from an allogenic donor will interfere with testing. For instructions for testing patients who have received a bone marrow transplant, call 800-533-1710.
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.
Additional Information: To ensure a minimum DNA amount and concentration, the preferred blood volume must be submitted. Testing may be canceled if the specimen supplied is inadequate.
Specimen Stability Information: Ambient (preferred) 4 days/Refrigerated 14 days
Prenatal Specimens
Due to its complexity, consultation with the laboratory is required for all prenatal testing; call 800-533-1710 to speak to a genetic counselor.
Submit only 1 of the following specimens:
Specimen Type: Amniotic fluid
Container/Tube:
Preferred: Screw-capped, sterile centrifuge tubes
Acceptable: T-25 flasks of confluent cultured cells
Specimen Volume: 20 mL
Specimen Stability Information: Refrigerated (preferred)/Ambient
Specimen Type: Chorionic villi
Container/Tube:
Preferred: 15-mL tube containing 15 mL of transport media
Acceptable: T-25 flasks of confluent cultured cells
Specimen Volume: 20 mg
Specimen Stability Information: Refrigerated
Specimen Type: Blood spot
Container/Tube:
Preferred: Collection card (Whatman Protein Saver 903 Paper)
Acceptable: Perkin Elmer 226 (formerly Ahlstrom 226) filter paper, or Blood Spot Collection Card
Specimen Volume: 5 Blood spots
Collection Instructions:
1. An alternative blood collection option for a patient >1 year of age is a finger stick.
2. Let blood dry on the filter paper at ambient temperature in a horizontal position for a minimum of 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, see Blood Spot Collection Instructions in Special Instructions.
2. For collection instructions in Spanish, see Blood Spot Collection Card-Spanish Instructions (T777) in Special Instructions.
3. For collection instructions in Chinese, see Blood Spot Collection Card-Chinese Instructions (T800) in Special Instructions.
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 in Special Instructions:
-Informed Consent for Genetic Testing (T576)
-Informed Consent for Genetic Testing-Spanish (T826)
2. Molecular Genetics: Congenital Inherited Diseases Patient Information (T521) in Special Instructions.
3. If not ordering electronically, complete, print, and send a Neurology Specialty Testing Client Test Request (T732) with the specimen.
Secondary ID
65575Useful For
First-tier newborn screening for spinal muscular atrophy (SMA)
Prenatal testing for SMA
Diagnostic testing to confirm a suspected diagnosis of SMA
Reflex Tests
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
CULAF | Amniotic Fluid Culture/Genetic Test | Yes | No |
CULFB | Fibroblast Culture for Genetic Test | Yes | No |
MATCC | Maternal Cell Contamination, B | Yes | No |
Testing Algorithm
For prenatal specimens only: If amniotic fluid (nonconfluent cultured cells) is received, amniotic fluid culture/genetic test will be added at an additional charge.
If chorionic villus specimen (nonconfluent cultured cells) is received, fibroblast culture for genetic test will be added per laboratory protocol at an additional charge.
For any prenatal specimen that is received, maternal cell contamination testing will be added per laboratory protocol at an additional charge.
If the patient has abnormal newborn screening result for spinal muscular atrophy, immediate action should be taken. Refer to the appropriate American College of Medical Genetics and Genomics Newborn Screening ACT Sheet(1).
The following algorithms are available:
-Inherited Motor Neuron Disease and Dementia Testing Algorithm
Special Instructions
- Molecular Genetics: Congenital Inherited Diseases Patient Information
- Informed Consent for Genetic Testing
- Hereditary Peripheral Neuropathy Diagnostic Algorithm
- Blood Spot Collection Card-Spanish Instructions
- Blood Spot Collection Card-Chinese Instructions
- Inherited Motor Neuron Disease Testing and Dementia Algorithm
- Informed Consent for Genetic Testing (Spanish)
- Spinal Muscular Atrophy Testing Algorithm
- Blood Spot Collection Instructions
Method Name
Dosage Analysis by Digital Droplet Polymerase Chain Reaction (ddPCR)
Reporting Name
SMA Diagnostic by Del/DupSpecimen Type
VariesSpecimen Minimum Volume
Blood: 1 mL
Amniotic Fluid: 10 mL
Chorionic villi: 5 mg
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Varies |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Reference Values
An interpretive report will be provided.
Day(s) Performed
Varies
Report Available
5 to 10 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
81329
88235 (if appropriate)
88240 (if appropriate)
88233 (if appropriate)
88240 (if appropriate)
81265 (if appropriate)
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
SMNDX | SMA Diagnostic by Del/Dup | 49857-6 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
113452 | Result Summary | 50397-9 |
113453 | Result | 49857-6 |
113454 | Interpretation | 69047-9 |
113455 | Additional Information | 48767-8 |
113456 | Specimen | 31208-2 |
113457 | Source | 31208-2 |
113458 | Released By | 18771-6 |