For the safety of our patients and employees in Texas, Oklahoma, Missouri and Arkansas, the current winter weather may affect patient service center hours. Please review the list of affected locations for further information.
Myotonic Dystrophy 2 (ZNF9/CNBP) Genetic Testing (Repeat Expansion)
Special Instructions
This assay is not currently available in New York state.
Expected Turnaround Time
14 - 28 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Specimen Requirements
Specimen
Whole blood
Volume
4 mL
Minimum Volume
1 mL
Container
Lavender-top (EDTA) tube
Collection
Draw blood into EDTA tube.
Storage Instructions
Ship ASAP, but stable up to 5 days post-collection at room temperature. Do not freeze.
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | 5 days |
Refrigerated | 5 days |
Frozen | Do not freeze |
Causes for Rejection
Frozen blood EDTA tube
Test Details
Use
Type 2 myotonic dystrophy results from a mutation in the CNBP gene known as a tetranucleotide repeat expansion. This mutation increases in size of the repeated CCTG segment in the CNBP gene. People with type 2 myotonic dystrophy have from 75 to more than 11,000 CCTG repeats.
Limitations
Maximum reportable sizing: 373 repeats.
This test was developed and its performance characteristics determined by LabCorp. It has not been cleared or approved by the Food and Drug Administration.
Methodology
Repeat-Primed PCR (QP-PCR)
© 2021 Laboratory Corporation of America® Holdings and Lexi-Comp Inc. All Rights Reserved.
CPT Statement/Profile Statement
The LOINC® codes are copyright © 1994-2021, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee. Permission is granted in perpetuity, without payment of license fees or royalties, to use, copy, or distribute the LOINC® codes for any commercial or non-commercial purpose, subject to the terms under the license agreement found at https://loinc.org/license/. Additional information regarding LOINC® codes can be found at LOINC.org, including the LOINC Manual, which can be downloaded at LOINC.org/downloads/files/LOINCManual.pdf