Specimen Requirements

Specimen Labeling

All specimens submitted for testing must be properly labeled with patient name, MRN/SSN, date collected, and name of physician.  Specimens must be accompanied by a CIS requisition or a DMCUL Molecular Genetics requisition form.

Causes for Sample Rejection:

We cannot accept serum, frozen whole blood, or samples that have been mis-labeled or are without labels.

Specimen required:

Peripheral blood:  3-6 ml whole blood into lavender (EDTA) top tubes (preferably in 2X3.5 ml tubes) of whole blood.  Sample amount for infants:  1-2 ml whole blood collected in lavender (EDTA) tubes.  Invert several times to mix with anticoagulant.  DO NOT FREEZE!

Amniotic fluid:  Discard the first 1-2 ml of aspirated amniotic fluid to reduce the risk of maternal cell contamination.  Obtain 10-20 ml amniotic fluid by amniocentesis.  Two or three sequentially numbered aliquots are requested.  Send to Cytogenetics Laboratory immediately after collection, preferably by overnight delivery.  If sending cultured amniotic fluid cells, 1-2 T-25 flasks are required.  Keep specimen at room temperature.  DO NOT FREEZE

Chorionic Villus:  Obtain 20-30 mg of chorionic villis (10 mg minimum) and place into sterile tube containing transport medium.  Send to Cytogenetics Laboratory immediately after collection, preferably by overnight delivery.  If sending cultured chorionic villus cells, 1-2 T-25 flasks are required.  Keep specimen at room temperature.  DO NOT FREEZE!

Paraffin embedded tissue:   Paraffin blocks with the highest percent of tumor to normal ratio are forward directly to the laboratory (preferably >30% of embedded tissue is tumor tissue); up to 40 microns will be used to isolate genomic DNA from the embedded tissue. The paraffin block will be returned to sender after the test is complete.

Bone Marrow:  1-2 ml freshly aspirated bone marrow into lavender (EDTA) top tube.  Invert several times to mix with anticoagulant.  DO NOT FREEZE!

Solid Tissue:  Submit 40-60 mg fresh or flash frozen tissue.  For skin specimens, punch biopsy is adequate for most tests.  Please contact the laboratory for specific test requirements.