Cytogenetics Specimen Info

SPECIMEN TRANSPORT

LABORATORY HOURS: 7 a.m. - 5:00 p.m. Monday-Friday, 7 a.m. - 3:30 p.m. Saturday, and as needed.
Specimens may be sent at any time. Please notify the laboratory at (612) 873-8548 during laboratory hours or at pager # (612) 336-0246 after hours, weekends, and holidays and we will arrange for specimen transportation.

Send Specimens to:

Cytogenetics Laboratory (612-873-8548)
Hennepin County Medical Center
2nd Floor North, Clinical Laboratory, Triage
701 Park Avenue
Minneapolis, MN 55415

All specimens should be left at room temperature and protected from temperature extremes during transport to the laboratory.

SPECIMEN COLLECTION AND REPORTING

The number of cells analyzed represents the routine study; additional cells are analyzed if clinically indicated.

Turnaround times (TAT) are listed as a range for 90% of the cases, with a mean for all cases in parentheses.

Amniotic Fluid Chromosome Study

• Specimen: 20-30 mL in sterile tissue culture tubes
• Analysis: 15 metaphase cells from 15 colonies
• Final TAT: 7-10 days (8)

Amniotic Fluid FISH for Aneuploidy

• Specimen: 2-3 mL of non-bloody amniotic fluid in a sterile tissue culture tube
• Analysis: 50 interphase nuclei
• Preliminary TAT: 1-2 days (1)

Peripheral Blood Chromosome

• Specimen: 2 mL (newborn) or 5 mL (child or adult) in sodium heparin
• Analysis: 20 metaphase cells
• Preliminary TAT (newborn): 1-3 days (2)
• Final TAT (newborn): 3-7 days (5)
• Final TAT (child or adult): 5-14 days (10)

Bone Marrow Chromosome

• Specimen: 2-5 mL in sodium heparin
• Analysis: 20 metaphase cells
• Preliminary TAT (stat): 1-2 days (1)
• Final TAT (stat): 2-4 days (3)
• Preliminary TAT (routine): 2-7 days (4)
• Final TAT (routine): 3-10 days (5)

Hematologic Blood Chromosome

• Specimen: 5 mL of blood in sodium heparin
• TAT: see bone marrow TATs

Malignant Tissue Chromosome

• Specimen: 5 mm³ of involved tissue in a sterile container of sterile saline or tissue culture media (do not place in fixative)
• Analysis: 20 metaphase cells
• Preliminary TAT: 2-10 days (5)
• Final TAT: 2-14 days (7)

Products of Conception (POC) Chromosome Study

• Specimen: Fetal tissue and chorionic villi (placenta) in a sterile container of sterile saline or tissue culture media (do not place in fixative); the specimen should be refrigerated if overnight storage is necessary
• Analysis: 20 metaphase cells
• Final TAT: 2-3 weeks (17 days)

Skin Biopsy Chromosome Study

• Specimen: 3-5 mm³ of tissue in a sterile container of sterile saline or tissue culture media
• Analysis: 20 metaphase cells
• Final TAT: 2-3 weeks (17 days)

Fluorescent in situ Hybridization (FISH)

• Specimen: amniotic fluid, blood, bone marrow, malignant tissue, products of conception, skin, or buccal smear
• Probes: centromere, telomere, whole chromosome paint, and unique sequence
• Assays: prenatal aneuploidy screening, microdeletion syndromes, marker chromosome identification, cancer chromosome rearrangements.

Tissue Culture for Send-Out Testing

• Various tissue types may be cultured to send out for other specialty testing.

Related Testing

• Triple screen, AFP, fetal lung maturity, as well as other testing, is available through the HCMC Clinical Laboratories.