FGFR2 - COMPLETE ANALYSIS
Gene Symbol: FGFR2
Chromosomal Locus: 10q26 .13
Protein: Fibroblast growth factor receptor 2
Pseudonyms: FGF receptor, protein tyrosine kinase, receptor-like, 14; TK14; Antley-Bixler syndrome, Apert syndrome, Beare-Stevenson, nonspecific Craniosynostosis, Crouzon syndrome, Jackson-Weiss syndrome, LADD syndrome, Pfeiffer syndrome, Saethre-Chotzen syndrome and Scaphocephaly with maxillary retrusion and mental retardation.
TURNAROUND TIME: 4 weeks
TESTING METHODOLOGY: PCR amplification and DNA sequencing of the entire coding region of the of the FGFR2 gene (FGFR2c isoform).
- Collect: Prefer two 5ml whole blood EDTA (lavender top) tube.
- Min. Collection: 0.7 ml whole blood EDTA.
- Transport: blood EDTA at Room Temp shipped regular next day air (No Saturday delivery; store specimen at 4°C and ship Monday).
- Stability: Ambient: up to 7 days; Refrigerated: 2 weeks. Frozen: unacceptable
- Unacceptable Conditions: Serum. Frozen or severely hemolyzed blood. Clotted blood.
- Prenatal testing: Direct: 5ml direct unspun amniotic fluid or 3mm3 CVS tissue with a backup flask growing. Culture: confluent T25 flask. Maternal blood sample is required for maternal cell contamination studies.
Counseling and informed consent are recommended for genetic testing. A consent form
is available as a resource but not required.
Incidence: 1 in 2,000 births for Craniosynostosis, 1 in 60,000 for Crouzon syndrome and 1 in 10,000 for Apert syndrome. LADD syndrome represents 10-20% of the mutations (not located in exons 8 & 10) in the gene excluding Apert syndrome cases.
Inheritance: May be spontaneous or inherited in an autosomal dominant manner. In the inherited form, the diseases are considered fully penetrant although variable expression is typical.
Disease Characteristics: premature closure of the sutures between the bones of the skull, causing unicoronal or bicoronal craniosynostosis or cloverleaf skull. Also distinctive facial features and variable abnormalities of the hands and feet.
Molecular Genetic Mechanism: A variety of missense, nonsense and insertion/deletion mutations have been described.
Clinical Sensitivity: up to 90% (including exons 8 & 10)
Analytical Sensitivity: 99%
Test Limitations: Deletions of the entire gene will not be detected. Rare diagnostic errors can occur due to primer or probe site mutations or rare polymorphisms.
INDICATIONS FOR USE:
- To determine the genetic basis for craniodysmorphology in an affected individual.
- The panel is designed to help discriminate between syndromes with overlapping clinical symptoms.
- Individuals at risk who wish prenatal diagnosis.