Ordering Recommendation

Confirm clinical or suspected diagnosis of achondroplasia.

Mnemonic
AD PCR
Methodology

Polymerase Chain Reaction/Fluorescence Resonance Energy Transfer

Performed

Mon, Thu

Reported

2-7 days

New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
Collect

Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).

Specimen Preparation

Do not freeze. Transport 3 mL whole blood. (Min: 1 mL)

Storage/Transport Temperature

Refrigerated.

Unacceptable Conditions

Serum. Frozen specimens. Hemolyzed specimens.

Remarks
Stability

Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable

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: PCR and fluorescent hybridization probes.
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.

Compliance Category

Laboratory Developed Test (LDT)

Note
Hotline History
N/A
CPT Codes

81401

Components
Component Test Code* Component Chart Name LOINC
0051267 Achondroplasia PCR 38413-1
2001290 Achondroplasia PCR Specimen 31208-2
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
Achondroplasia (FGFR3) 2 Mutations