Test ID SCAP Spinocerebellar Ataxia Repeat Expansion Panel, Varies
Shipping Instructions
Specimen preferred to arrive within 96 hours of collection.
Specimen Required
Specimen Type: Whole blood
Patient Preparation: A previous bone marrow transplant from an allogenic donor will interfere with testing. Call 800-533-1710 for instructions for testing patients who have received a bone marrow transplant.
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 whole blood specimen in original tube. Do not aliquot.
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. Molecular Genetics: Neurology Patient Information
3. If not ordering electronically, complete, print, and send a Neurology Specialty Testing Client Test Request (T732) with the specimen.
Useful For
Molecular confirmation of clinically suspected spinocerebellar ataxia when a specific subtype isn’t suspected
Genetics Test Information
This test assesses for CAG repeat expansions within the ATXN1, ATXN2, ATXN3, CACNA1A, and ATXN7 genes, associated with spinocerebellar ataxia (SCA) type 1, SCA2, SCA3, SCA6, and SCA7. Additionally, testing for ATXN1 assesses for CAT trinucleotides that interrupt the CAG repeat tract.
Special Instructions
Method Name
Polymerase Chain Reaction (PCR)
Reporting Name
Spinocerebellar Ataxia PanelSpecimen Type
VariesSpecimen Minimum Volume
0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Ambient (preferred) | ||
Frozen | |||
Refrigerated |
Reference Values
SPINOCEREBELLAR ATAXIA TYPE 1
Normal alleles: <36 CAG repeats
Normal alleles with CAT interruptions: 36-43 repeats
Intermediate alleles without CAT interruptions: 36-37 repeats
Uncertain significance: 38 repeats
Expanded alleles without CAT interruptions: >38 CAG repeats
Expanded alleles with CAT interruptions: >43 CAG repeats
SPINOCEREBELLAR ATAXIA TYPE 2
Normal alleles: <32 repeats
Uncertain significance: 31 homozygous and 32 repeats
Reduced penetrance: 33-34 repeats
Expanded alleles: >34 repeats
SPINOCEREBELLAR ATAXIA TYPE 3
Normal alleles: <45 repeats
Intermediate alleles: 45-59 repeats
Expanded alleles: >59 repeats
SPINOCEREBELLAR ATAXIA TYPE 6
Normal alleles: <19 repeats
Intermediate alleles: 19 heterozygous repeats
Uncertain significance: 19 homozygous repeats
Expanded alleles: >19 repeats
SPINOCEREBELLAR ATAXIA TYPE 7
Normal alleles: <19 repeats
Uncertain significance: 19-27 repeats
Intermediate alleles: 28-33 repeats
Reduced penetrance: 34-36 repeats
Expanded alleles: >36 repeats
An interpretive report will be provided.
Day(s) Performed
Monday, Wednesday
Report Available
21 to 28 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
81178
81179
81180
81181
81184
81479 (if appropriate for government payers)
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
SCAP | Spinocerebellar Ataxia Panel | In Process |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
609506 | Result Summary | 21769-5 |
609507 | Result | 36911-6 |
609508 | Interpretation | 69047-9 |
609509 | Additional Information | 48767-8 |
609510 | Specimen | 31208-2 |
609511 | Source | 31208-2 |
609512 | Method | 85069-3 |
609513 | Disclaimer | 62364-5 |
609514 | Released By | 18771-6 |