Aneuploidy Detection, Products of Conception (POC), FISH
Screening for the common chromosomal aneuploidies (13, 15, 16, 18, 21, 22, X, and Y) in POC when fresh tissue is not available for full chromosome analysis
Rapid detection of common chromosomal aneuploidies or triploidy
Determining the genetic cause of a miscarriage
Genetics Test Information Provides information that may help with selection of the correct test or proper submission of the test request
If chromosome analysis on products of conception is not successful, this FISH test will be run automatically.
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Products of conception (POC) are tissues created at conception that spontaneously miscarry; these tissues include chorionic villi, fetal membranes, or fetal tissue. Spontaneous miscarriages occur in 15% to 20% of all recognized human conceptions. While there are many possible causes for miscarriages, chromosome anomalies can be identified in up to 50% of first-trimester miscarriages. It is important to determine a possible chromosomal cause of the pregnancy loss as this information impacts patient management and facilitates understanding of the reason for the loss.
Chromosomal aneuploidy, the gain or loss of chromosomes, is a major cause of early fetal demise. Trisomy is the most common type of chromosome abnormality in spontaneous abortions and has been observed for most chromosomes, with 13, 15, 16, 18, 21, 22, X, and Y being the most common.
Conventional chromosome analyses of POC (#8887 Chromosome Analysis, Autopsy, Products of Conception, or Stillbirth) is a commonly performed method used to identify these common chromosome aneuploidies. Conventional chromosome analysis involves fibroblast cultures. Unfortunately, 20% of POC specimens fail to grow when cultured. A FISH method has been developed to analyze this subset of cases or to be used when fresh tissue is not available for full chromosome analysis.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
An interpretive report will be provided.
Aneuploidy is detected when the percent of cells with an abnormality exceeds the normal reference range for any given probe.
An interpretive report is provided.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
This test has not been approved by the FDA and is best used as an adjunct to existing clinical and pathological information.
The specificity of these probes is estimated to be 100% with no cross hybridizations. To establish the analytic sensitivity, analysis was based on 37 products of conception specimens. Chromosome analysis was unsuccessful for 8 of the 37 specimens. For the remaining 29 cases, the correct FISH result was obtained when compared to chromosome analysis.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
Warburton D, Byrne J, Canki N: Chromosome anomalies and prenatal development: An atlas. In Oxford Monographs on Medical Genetics. New York, Oxford University Press, 1991, pp 2-3, 57-62