Blood

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

10 mL whole blood required for adults
2-5 mL whole blood required for infants or small children

Whole blood sample should arrive at referral lab within 48 hours of collection; viable for FIVE days at room temperature.

Collect samples Monday-Wednesday only; no weekends, no holidays, or no day before a holiday collection.

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.

81479