FISH Analysis -Neurofibromatosis Type 1
Use
FISH Analysis - Neurofibromatosis Type 1 is a diagnostic test aimed at identifying chromosomal deletions related to neurofibromatosis type 1 (NF1). Approximately 5% of NF1 patients show deletions in the NF1 gene, with rates as high as 20% in those with severe manifestations. Most individuals carry other deleterious variants not captured by this FISH method, hence initial screening with Chromosome Microarray Analysis and NF1 gene sequencing is advised. As an autosomal dominant disorder, NF1 may lead to a variety of symptoms, such as multiple neurofibromas and pigmentary abnormalities. Understanding one's NF1 status permits clinicians to devise appropriate management strategies for patients and their families.
Special Instructions
This FISH assay specifically identifies chromosomal deletions related to NF1. It requires the use of Sodium Heparin tubes for sample collection and must be shipped at room temperature, ensuring arrival at the lab within 48 hours. Patients are advised to inform their healthcare provider about any medications or health conditions that might affect the sample integrity prior to collection. Initial screening should be conducted with Chromosome Microarray Analysis - High Resolution to maximize detection efficacy. Healthcare providers should ensure proper coordination to facilitate swift testing and results for patients exhibiting symptoms of NF1.
Limitations
The FISH assay specifically assesses the presence or absence of the NF1 gene and cannot detect other types of genetic rearrangements or mutations present in this condition. A normal result does not rule out other possible genetic alterations within the NF1 gene that might be important for diagnosis and treatment planning. This method is limited in scope and should be considered a part of a broader diagnostic approach including DNA sequencing and chromosome microarray analysis.
Methodology
Chromosomal / Cytogenetics (FISH)
Biomarkers
Result Turnaround Time
14 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood (Fresh)
Volume
3-5 cc
Minimum Volume
1-2 cc
Container
Sodium Heparin tube (Green-Top)
Collection Instructions
Draw blood in a Sodium Heparin (green-top) tube(s).
Storage Instructions
Ship the sample at room temperature to the laboratory by overnight express.
Causes for Rejection
EDTA and plasma separator tubes (PST) are not acceptable for cytogenetic analysis.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Specimen should arrive in the laboratory within 48 hrs of sample date. |
| Frozen | Specimen cannot be frozen. |
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