ARUP's Laboratory Test Directory

Thanatophoric Dysplasia, Types 1 & 2 (FGFR3) 13 Mutations : 0051506
[ image for: Patient History For Molecular Genetic Testing]
Patient History For Molecular Genetic Testing
  


Mnemonic: TD PAN

Methodology: Polymerase Chain Reaction/Fragment Analysis
Performed: Sun-Sat
Reported: 3-7 days
Specimen Required: 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.

Stability (collection to initiation of testing): Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Interpretive Data: Background information for Thanatophoric Dysplasia, Types I and II (FGFR3) 13 Mutations
Characteristics:
Micromelia, macrocephaly, short ribs and a narrow thorax; TD I has bowed femurs and TD II has straight femurs and a cloverleaf skull; death usually occurs from respiratory insufficiency within hours or days of birth.
Incidence:
1 in 20,000 to 50,000 births.
Inheritance:
Autosomal dominant; arising from a de novo mutation.
Cause:
Fibroblast growth factor receptor 3 (FGFR3) gene mutations.
Mutations tested:
c.742C>T (R248C), c.746C>G (S249C), c.1108G>T (G370C), c.1111A>T (S371C), c.1118A>G (Y373C), c.2419T>G (X807G), c.2419T>A (X807R), c.2420G>T (X807L), c.2420G>C (X807S), c.2421A>T (X807C), c.2421A>C (X807C) and c.2421A>G (X807W) for TD I and c.1948A>G (K650E) for TD II.
Clinical Sensitivity and Specificity:
99 percent.
Methodology:
Polymerase chain reaction (PCR) and single nucleotide extension followed by capillary electrophoresis.
Analytic Specificity and Sensitivity
: 99 percent.
Limitations:
Mutations other than those targeted in FGFR3 will not be detected; analytic sensitivity may be compromised by rare primer site mutations.

This test is performed pursuant to an agreement with Roche Molecular Systems, Inc.



Counseling and informed consent are recommended for genetic testing. Consent forms are available online at www.aruplab.com.

Refer to Statement C under Testing Information at http://www.aruplab.com.
CPT Code(s): 83891 Isolation; 83900 Multiplex amplification; 83901 x2 Additional amplification; 83914 x9 Extension; 83909 Capillary electrophoresis; 83912 Interpretation and report - Additional CPT code modifiers may be required for procedures performed to test for oncologic or inherited disorders.
Cross References: TD (Thanatophoric Dysplasia, Types 1 & 2 (FGFR3) 13 Mutations)
 
 

 

 

 
All ARUP Sites:        www.aruplab.com     ·     www.arupconsult.com     ·     www.arup.utah.edu     ·     www.childx.org     ·     www.utahblood.org