Ordering Recommendation
Confirm clinical or suspected diagnosis of achondroplasia.
Mnemonic
Methodology
Polymerase Chain Reaction/Fluorescence Monitoring
Performed
Mon, Thu
Reported
2-7 days
New York DOH Approval Status
Specimen Required
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
Do not freeze. Transport 3 mL whole blood. (Min: 1 mL)
Refrigerated.
Serum. Frozen specimens in glass collection tubes. Hemolyzed specimens.
Ambient: 72 hours; Refrigerated: 1 week; Frozen: 1 month
Reference Interval
By report
Interpretive Data
Background information for Achondroplasia (FGFR3) 2 Mutations:
Characteristics: Short stature with disproportionately short arms and legs, a large head, usually normal life span and intelligence; increased risk for death in infancy from compression of spinal cord and/or upper airway obstruction.
Incidence: 1:25,000
Inheritance: Autosomal dominant; 80 percent arise from de novo mutations.
Penetrance: 100 percent
Cause: Pathogenic FGFR3 gene mutation
Clinical Sensitivity: Two mutations, c.1138G>A and c.1138G>C, in the FGFR3 gene account for greater than 99 percent of cases.
Methodology: Polymerase Chain Reaction (PCR) and fluorescence monitoring.
Analytical Sensitivity and Specificity: Greater than 99 percent
Limitations: Mutations other than c.1138G>A and c.1138G>C will not be detected. Diagnostic errors can occur due to rare sequence variations.
This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
Laboratory Developed Test (LDT)
Note
Hotline History
Hotline History
CPT Codes
81401
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
0051267 | Achondroplasia PCR | 38413-1 |
2001290 | Achondroplasia PCR Specimen | 31208-2 |