Freeman-Sheldon Syndrome (MYH3) Sequencing Exon 17
2002662
Ordering Recommendation
Diagnostic testing for Freeman-Sheldon syndrome.
Mnemonic
FSS SEQ
Methodology
Polymerase Chain Reaction/Sequencing
Performed
Varies
Reported
7-14 days
New York DOH Approval Status
Specimens from New York clients will be sent out to a New York DOH approved laboratory, if possible.
ARUP Consult®
Disease Topics
Specimen Required
- Patient Preparation
- Collect
- Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 1 mL)
- Storage/Transport Temperature
- Refrigerated.
- Unacceptable Conditions
- Remarks
- Stability
- Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Reference Interval
Interpretive Data
Background Information for Freeman-Sheldon Syndrome (MYH3) Sequencing Exon 17:
Characteristics: "Whistler appearance" due to facial muscle contractures, joint contractures of hands and feet, facial dysmorphism, strabismus, dental crowding, restricted cervical flexion, scoliosis, hearing loss, cryptorchidism and inguinal hernia.
Prevalence: Uncertain; approximately 100 cases have been reported to date.
Inheritance: Autosomal dominant.
Cause: Pathogenic MYH3 gene mutations.
Clinical Sensitivity: Approximately 70 percent.
Methodology: Bidirectional sequencing of MYH3 exon 17 which includes the two most common mutations, R672C and R672H.
Analytical Sensitivity and Specificity: 99 percent.
Limitations:Diagnostic errors can occur due to rare sequence variations. Mutations outside exon 17 will not be detected.
Characteristics: "Whistler appearance" due to facial muscle contractures, joint contractures of hands and feet, facial dysmorphism, strabismus, dental crowding, restricted cervical flexion, scoliosis, hearing loss, cryptorchidism and inguinal hernia.
Prevalence: Uncertain; approximately 100 cases have been reported to date.
Inheritance: Autosomal dominant.
Cause: Pathogenic MYH3 gene mutations.
Clinical Sensitivity: Approximately 70 percent.
Methodology: Bidirectional sequencing of MYH3 exon 17 which includes the two most common mutations, R672C and R672H.
Analytical Sensitivity and Specificity: 99 percent.
Limitations:Diagnostic errors can occur due to rare sequence variations. Mutations outside exon 17 will not be detected.
Compliance Statement C: The performance characteristics of this test were validated by ARUP Laboratories. The U.S. Food and Drug Administration (FDA) has not approved or cleared this test. However, FDA approval or clearance is currently not required for clinical use of this test. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions. ARUP is authorized under Clinical Laboratory Improvement Amendments (CLIA) and by all states to perform high-complexity testing. Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
Note
CPT Code(s)
Components
| Component Test Code* | Component Chart Name | LOINC |
|---|---|---|
| 2002663 | FSS SEQ Specimen | |
| 2002664 | Freeman-Sheldon Syndrome Interpretation |
Aliases
- Whistling Face Syndrome