RB1 Gene Analysis Full Sequence, Unilateral, Tumor
Label Mnemonic: RB1TB
Epic code: LAB7507
Downtime form: A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery
Commercial Mailout Laboratory
6240-8 RCP
356-8593
Specimen(s):
Blood + Tumor Tissue
Collection Medium:
and and or and
Pink top tube 6 mL (K2-EDTA) Pink top tube 6 mL (K2-EDTA) Sterile Tissue Culture Tube Lavender top tube 3 mL (EDTA) Lavender top tube 3 mL (EDTA)
Minimum:
For adults, TWO 6 mL blood in EDTA pink top tubes
For infants or small children, 2-5 mL blood in EDTA lavender top tubes

Tumor is placed in sterile tissue culture media with antibiotics added.

10 mL whole blood required for adults
2-5 mL whole blood required for infants or small children
Delivery Instructions:
Whole blood and fresh tumor should arrive at referral lab within 48 hours of collection; viable for FIVE days at room temperature. To extend tumor viability, refrigerate until shipped. If tumor shipment is delayed or if media is yellow in color, contact clinical team.
Testing Schedule:
Collect samples Monday-Wednesday only; no weekends, no holidays, or no day before a holiday collection.
Comments:
This mailout test requires pathologist approval for orders during inpatient encounters. Mailouts staff will not process order without approval. The pathologist covering mailouts approval can be reached at pager #3724. If approval is given, the name of the pathologist can be selected in the drop-down menu to the right of the approval warning in Epic when ordering the test.

Please print, complete and submit the Retinoblastoma Genetic Test Requisition and the Informed Consent to Perform Genetic Testing from Impact Genetics to the lab, with the specimen.

Diagnosis of Unknown Mutations in the RB1 gene
*DNA is isolated from blood or retinoblastoma tumor.
*The size and copy number of each of the 27 exons and promoter region
 of the RB1 gene is determined by quantitative multiplex PCR.
*The DNA sequence is analyzed.
*In isolated cases of unilateral retinoblastoma, methylation-specific 
*PCR is used to identify promoter hypermethylation.
*If other methods detect no mutation RT-PCR is used to search for
 intronic mutations likely to cause missplicing that leads to exon
 skipping.
*Results are confirmed and reported.

Testing Relatives for a Known Mutation
*DNA is isolated from a blood sample.
*One relatively simple test determines the presence or absence of the
 mutation found in the proband.
CPT Code:
81479