Hereditary Retinoblastoma (RB1) Sequencing and Deletion/Duplication
Also known as: RB1 NGS
Use
This test is recommended for individuals with a suspected diagnosis or family history of heritable retinoblastoma. Hereditary retinoblastoma is a malignant tumor of the retina caused by a single germline pathogenic variant in the RB1 gene, predisposing individuals to retinoblastoma and other nonocular tumors, including pinealoblastoma, osteosarcoma, soft tissue sarcoma, and melanoma. Early diagnosis through genetic testing assists in medical screening, management, and identifying at-risk family members.
Special Instructions
A Hereditary Cancer Testing Patient History Form and informed consent for genetic testing are required for New York patients. Specimens from New York clients are sent out to a state-approved laboratory. Ambient stability and storage conditions differ for New York State clients.
Limitations
The test detects variants within the coding regions and intron-exon boundaries of the RB1 gene, but deletions/duplications/insertions of any size may not be detected by massively parallel sequencing. Regulatory region and deep intronic variants will not be identified. Precise breakpoints for large deletions or duplications are undetermined, and single exon deletions/duplications may not be detected based on the rearrangement breakpoints. Diagnostic errors may occur due to rare sequence variations, pseudogenes, repetitive, or homologous regions. The test does not detect low-level mosaic or somatic variants, gene conversion events, complex inversions, translocations, mitochondrial DNA variants, or repeat expansions. Noncoding transcripts were not analyzed, and certain exons may have reduced sequencing sensitivity.
Methodology
NGS ( Targeted)
Biomarkers
Result Turnaround Time
10-15 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
3 mL
Minimum Volume
3 mL
Container
Lavender or pink (EDTA) or yellow (ACD solution A or B)
Storage Instructions
Refrigerated
Causes for Rejection
Serum or plasma; grossly hemolyzed or frozen specimens; saliva; buccal brush or swab, FFPE tissue.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours (48 hours for New York State Clients) |
| Refrigerated | 1 week (2 weeks for New York State Clients) |
| Frozen | Unacceptable |