ABSTRACT
OBJECTIVE: To determine the fetal aneuploidy in fetal blood cells from cordocentesis. METHODS: We analyzed their karyotype and performed fluorescence in situ hybridization(FISH) for chromosome 18, 21, X, and Y in 14 cases of fetal blood cells from cordocentesis at Department of Obstetrics & Gynecology, College of Medicine, Seoul National University and Hamchoon Women's Clinic. RESULTS: In all cases we obtained the consistent results in both methods and were able to rapidly detect aneuploidy in uncultured fetal blood cells using FISH before karyotyping with culture for 48 hr. The averages for accuracy of FISH were from 84.6 % to 93.9%. CONCLUSION: In this study we suggest that the rapid detection in uncultured fetal blood using FISH is possible and that this diagnostic method will be clinically useful when rapid result would be demanded.
Subject(s)
Aneuploidy , Chromosomes, Human, Pair 18 , Cordocentesis , Fetal Blood , Fluorescence , Gynecology , In Situ Hybridization , Karyotype , Karyotyping , Obstetrics , SeoulABSTRACT
OBJECTIVE: The cytogenetic analysis for earlier detection of fetal chromosome aneuploidies is performed from chorionic villus using either long-term culture or direct chromosome preparation. To analyze the cause of pregnancy loss, we also attempt the cytogenetic study in product of conception(POC) using chorionic villi or fetal tissue. But the failure of analysis often occurs in direct preparation of villus cells and product of conception(POC). We studied to evaluate the clinical usefulness of FISH in uncultured chorionic villus cells of culture-failed cases. METHODS: According to the patient's indication, we performed FISH for chromosome 18, 21, X and Y in chorionic villi as well as POC and compared FISH results with their chromosomal studies. RESULTS: We found one trisomy 18 and one trisomy 21 in Chorionic Villus Sampling and one trisomy 18 and one monosomy X(45, X) in POC. The averages for accuracy of FISH were 83-91% and all cases are represented consistent results with their chromosomal studies. Among them, we could analyze using FISH only in 5 cases of culture failure including one case of monosomy X in POC. CONCLUSION: We could detect aneuploidy with uncultured chorionic villus cells in case of culture failure, using FISH, it may be the potential method to assist the cytogenetic study.
Subject(s)
Female , Pregnancy , Aneuploidy , Chorion , Chorionic Villi Sampling , Chorionic Villi , Chromosomes, Human, Pair 18 , Cytogenetic Analysis , Cytogenetics , Down Syndrome , Fetus , Monosomy , Trisomy , Turner SyndromeABSTRACT
FISH is suggested as a possible method to detect the numerical and structural abnormalities of chromosomes in interphase nucleus. We performed this study to discuss the clinical usefulness of FISH in uncultured amniocytes and to set up the cut-off value for further study. We collected amniotic fluid samples from patients whose chromosome studies were recommended due to screen positive for Down and Edword syndrome in triple marker test using maternal serum. The centromeric probe for chromosome 18 and the locus-specific probe for chromosome 21 were used and the results were compared to their karyotypes. We could find 2 cases of trisony 21 and 2 cases of trisony 18 and the other cases represented normal karyotypes. The accuracies were 91% for disomy 18, 89% for trisomy 18, 92% for disomy 21 and 88% for trisomy 21. Therefore FISH technique is a possible method to detect the chromosomal abnormalities in uncultured amniocytes and the use of locus-specific probe for chromosome 21 would be more useful for detecting the aneuploidy of chromosome 21 than 13/21 centromeric probe.
Subject(s)
Female , Humans , Amniotic Fluid , Aneuploidy , Chromosome Aberrations , Chromosomes, Human, Pair 18 , Chromosomes, Human, Pair 21 , Down Syndrome , Fluorescence , In Situ Hybridization , In Situ Hybridization, Fluorescence , Interphase , Karyotype , TrisomyABSTRACT
Genetic amniocenteses were performed in a series of 127 patients as a routine study. Samples from the patients were cultured by in situ method, flask method or both according to the state of amniotic fluid. The overall success rate of culture was 97.6% and no culture failure was observed in the flask method. It took 5 days first of all and 8.15 days average from set-up to harvest and there were 7.2 colonies per dish in in situ method. Therefore, it is suggested that in situ method which decreased the mean culture days and made clonal analyses possible, is a clinically available and even more reliable method in parallel with flask method in prenatal diagnosis.
Subject(s)
Female , Humans , Amniocentesis , Amniotic Fluid , Prenatal DiagnosisABSTRACT
No abstract available.