Fluorescence in situ hybridization for prenatal screening of chromosomal aneuploidies

Results of a prenatal aneuploidy screening in uncultured amniocytes using FISH are available within a few hours. Thus, this so-called prenatal quick test is nowadays routinely and successfully applied to reduce psychological distress for pregnant women. The application of molecular cytogenetics for the prenatal screening of chromosomal aneuploidies overall is very reliable and has, compared with other (e.g., PCR-based) approaches, the advantage that analyses are performed on the single-cell level. Thus, cellular mosaics can also be picked up. Even though there are tendencies to apply the prenatal screening of chromosomal aneuploidies exclusively, we strongly support the recommendation of the German Society of Human Genetics, that this kind of test should only be used as a preamble to full chromosome analysis by microscopy to avoid pitfalls.