Application of FISH(Fluorescence In Situ Hybridization) in uncultured chorionic villus cells / 대한산부인과학회잡지

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.

Clinical Significance of Amniotie Fluid Cell Culture Failure / 대한주산의학회잡지

The reports of all amniocentesis samples received in our cytogenetic laboratory from 1986 to 1998 were reviewed to identify cases in which culture failure of amniocytes occurred. Medical records were then reviewed for the prenatal ultrasonographic findings, karyotype when available, and clinical outcome. We investigated the clinical aspects associated with second trimester amniotic fluid cell culture failure. During the study period, 5,325 second trimester amniotic fluid samples were processed, of which 42(0.8%) failed to yield a result. Ninety-seven percent of the samples were obtained before 24 weeks' gestation, mainly because of advanced maternal age. Three percent of the samples were obtained after 24 weeks' gestation. Culture failure was more common in samples obtained after or at 24 weeks' gestation(11.8%) than in those obtained before 24 weeks(0.44%)(p<0.05, chi-square test). This difference was also observed when the results were analysed according to the cases with known normal or abnormal karyotypes, The frequency of culture failure did not differ significantly between the groups with normal and abnormal karyotypes. We conduded that amniotic fluid cell culture failure is more common in advanced pregnancy and is not associated with a higher incidence of chromosomal abnormalities.