Rapid prenatal diagnosis of aneuploidies in uncultured amniocytes by fluorescence in situ hybridization. Evaluation of >3,000 cases.
OBJECTIVE
A new method in prenatal diagnostics allows to demonstrate certain numeric chromosomal aneuploidies in amniotic cells within 24 h in contrast to conventional methods which take 1-3 weeks.


METHODS
The experience with this rapid fluorescence in situ hybridization (FISH) method is compared to standard karyotyping and its clinical relevance is described in a large clinical pilot study. FISH on uncultured amniocytes has been performed from 12 weeks of gestation to the third trimester using commercially available chromosome-specific DNA probes for chromosomes 13, 18, 21, X and Y.


RESULTS
FISH was performed successfully in 3,150 prenatal cases. All trisomies 13, 18 and 21 and all cases with gonosomal aberrations were detected by FISH analysis. Neither false-positive nor false-negative results were obtained using FISH. For all analyzable disorders the FISH results were in complete agreement with standard cytogenetics.


CONCLUSIONS
In our experience, FISH is a valuable and reliable method for rapid diagnosis of numeric chromosomal aneuploidies.
Institut für Klinische Genetik und Frauenklinik am Evangelischen Krankenhaus Oberhausen, Deutschland, Germany. eiben@cityweb.de
B
B
Eiben
W
W
Trawicki
W
W
Hammans
R
R
Goebel
M
M
Pruggmayer
J T
JT
Epplen
D000328:Adult; D000649:Amniocentesis / Q000379:methods*; D000782:Aneuploidy; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D007621:Karyotyping; D008297:Male; D009030:Mosaicism; D010865:Pilot Projects; D011123:Polyploidy; D011247:Pregnancy; D014314:Trisomy; D014960:X Chromosome; D014998:Y Chromosome