Test ID: POC    
Chromosome Analysis, Autopsy, Products of Conception, or Stillbirth

Autopsy:

The specimen is cleaned and cut into small pieces and treated with enzymes. The tissue is then placed into a dish with a coverslip. Cells are cultured with Chang and MEM-alpha-medium containing 20% fetal bovine serum and antibiotics to establish a fibroblast culture. After 5 to 14 days, the fibroblasts are exposed to colcemid, ethidium bromide, and hypotonic solution, and fixed with glacial acetic acid and methanol. Metaphase cells are dropped onto microscope slides and are routinely stained by G-banding, but other staining methods are frequently employed as needed. At least 20 metaphases are examined for structural and numeric chromosome abnormalities. Minimal evidence for the presence of an abnormality is defined as 2 or more metaphases with the same structural abnormality or chromosome gain (trisomy), or 3 or more metaphases lacking the same chromosome. Five to 10 metaphases are captured using a computer-based imaging system and karyograms are prepared from 2 or more representative metaphases. (Dewald GW: Chromosome study of autopsy tissue. In Current Methods of Autopsy Practice. 2nd edition. Edited by J Ludwig. Philadelphia, WB Saunders Company, 1979, pp 155-159)

Products of Conception or Stillbirth:

Fetal versus maternal tissue is identified whenever possible. This tissue is cut into small pieces and treated with enzymes. The tissue is then placed into a Petri dish with a coverslip. Cells are cultured with Chang and MEM-alpha-medium containing 20% fetal bovine serum and antibiotics to establish a fibroblast culture. After 5 to 14 days, the fibroblasts are exposed to colcemid, ethidium bromide, and hypotonic solution, and fixed with glacial acetic acid and methanol. Metaphase cells are dropped onto microscope slides and are routinely stained by G-banding, but other staining methods are frequently employed as needed. At least 20 metaphases are examined. Minimal evidence for the presence of an abnormality is defined as 2 or more metaphases with the same structural abnormality or chromosome gain (trisomy), or 3 or more metaphases lacking the same chromosome. Five to 10 metaphases are captured using a computer-based imaging system and karyograms are prepared from 2 or more representative metaphases.  (Dewald GW: Chromosome study of autopsy tissues. In Current Methods of Autopsy Practice. 2nd edition. Edited by J Ludwig. Philadelphia, WB Saunders Company, 1979, pp 155-159; Spurbeck JL, Carlson RO, Allen JE, Dewald GW:  Culturing and robotic harvesting of bone marrow, lymph nodes, peripheral blood, fibroblasts, and solid tumors with in situ techniques. Cancer Genet Cytogenet 1988;32:59-66, Lindor NM, Ney JA, Gaffey TA, et al: A genetic review of complete and partial hydatidiform moles and nonmolar triploidy. Mayo Clin Proc 1992;67:791-799)

Samples processed Monday through Sunday. Results reported Monday through Friday, 8 a.m.-5 p.m. CST.