Fetal and Solid Tissue
The certified technologists at Diagnostic Cytogenetics, Inc. are experts at culturing your fetal and solid tissue specimens. We also offer FISH testing for the most common aneuploidies seen in pregnancy loss.
Indication for Testing
Products of conception:
• Pregnancy loss and advanced maternal age.
• Pregnancy loss with a history of multiple miscarriages (3 or more).
• Fetus with multiple congenital abnormalities that is suggestive of a chromosomal defect.
• Previous or family history of chromosomal abnormality.
• Confirmation of prenatal diagnosis.
• Tissue-specific mosaicism.
• Pallister-Killian syndrome.
Chromosome Analysis Detects:
• Aneuploidy (monosomy, trisomy)
• Deletions and duplications (>5Mb)
Chromosome Analysis Does Not Detect:
• Deletions or duplications that are too small to be seen by microscope (<5Mb)
G-banded chromosomes from 20 metaphase cells are examined. 5 cells are completely analyzed and at least 3 karyograms are prepared. Additional chromosome analysis and special banding techniques are employed as needed. If mosaicism is suspected, G-banded chromosomes from at least 50 cells are examined.
If there is no growth seen in culture on fetal tissue samples, the POC Aneuploidy FISH panel can be performed on cells saved from the original sample to rule out the common chromosome aneuploidies: 13, 16, 18, 21, 22, X, and Y (See FISH tab).
Please see our FISH page for our full test menu.
POC Aneuploidy FISH Panel
The POC Aneuploidy Fluorescent In Situ Hybridization (FISH) panel detects the most common chromosome gains and losses seen prenatally. This FISH panel can be performed on saved cells to rule out these aneuploidies on fetal tissue samples that do not grow adequately in culture to perform a chromosome analysis. It can also be ordered concurrently with cytogenetic analysis if rapid results are desired.
Probe Target Abnormality RB1 Trisomy 13 16qhet Trisomy 16 D18Z1 Trisomy 18 D21S259 Trisomy 21 BCR Trisomy 22 DXZ1 Sex Chromosome Aneuploidy DYZ3 Sex Chromosome Aneuploidy
Microdeletion/Microduplication Syndrome Probes
FISH on metaphase cells can also be performed to identify the following microdeletion/microduplication syndromes:
Syndrome Name Chromosome Location Probe/Gene Locus Wolf-Hirschhorn syndrome 4p16.3 D4S96 Cri du chat syndrome 5p15.2 D5S23 Williams syndrome 7q11.23 Elastin Retinoblastoma 13q14.2 RB1 Prader-Willi/Angelman syndrome 15q11.2-q13 SNRPN/D15S10 Smith-Magenis syndrome 17p11.2 FLI1 and RAI1 Miller-Dieker syndrome 17p13.3 LIS1 22q11.2 Deletion Syndrome (DiGeorge, Velocardiofacial Syndrome) 22q11.2 TUPLE1 (D22S553, D22S609, D22S942) Steroid Sulfatase Deficiency/X-linked Ichthyosis Xp22.3 STS Kallmann Syndrome 1 Xp22.3 KAL1
Fluorescence in-situ Hybridization (FISH) utilizes DNA probes that bind to a specific region of a chromosome. These probes produce bright colored signals that are examined on a fluorescence microscope. For metaphase FISH, ten to fifty cells are scored (depending on the probe used). For interphase FISH, two hundred cells are scored.
Test Turnaround Time* CPT Codes** Chromosome Analysis- POC 7-14 days (10.7 average) 88233, 88262, 88280, 88291 Chromosome Analysis- POC, Mosaic Results 7-14 days 88233, 88261, 88280×2, 88285, 88291 Chromosome Analysis- Skin Biopsy 7-14 days 88233, 88262, 88280, 88291 POC Aneuploidy FISH 24 hours 88377×3 Metaphase FISH 7-14 days (reported with chromosome analysis) 88377
*All turnaround times are business days from specimen receipt to report issued. Averages include weekends and holidays.
**Some codes may vary or be charged in multiple units, depending on patient-specific testing parameters.
If no cells are available for analysis, only set up fees will be billed.
Submitting a Sample
All solid tissue samples should be collected aseptically and transported in tissue culture media or Hank’s balanced salt solution. DCI can provide transport media upon request. Do NOT put in water, fixative, formalin or saline. Please keep sample at room temperature.
Products Of Conception/Fetal Tissue: Large chorionic villi sample (approximately 1-3 cm3) and a fetal tissue sample such as skin, lung, or pericardium. Please send multiple tissue types if possible. Label each tube with tissue type or origin.
Skin Biopsy/Solid Tissue: 1-3 mm3 or more tissue. Label tube with tissue type or origin.