The Replacement of Cytogenetic Analysis by Direct Chorionic Villi Sampling Preparation with Quantitative Fluorescence PCR

Abstract

Aim: The aim of this study is to assess the replacement of chromosomal analysis of chorionic villi (CV) direct preparation samples (DIR) by quantitative fluorescence PCR (QF-PCR) and to determine its advantages in routine prenatal diagnosis. Methods: From a total of 4,020 CV samples, rapid results were obtained either by conventional cytogenetic analysis of DIR in 2,770 samples, or by QF-PCR analysis in 1,250 samples. The final results were given after long-term culture (LTC). Results: The frequencies of unbalanced fetal karyotypes were not significantly different, being 4.8% by DIR-LTC and 4.3% by QF-PCR-LTC. No false-negative or false-positive results were obtained from either approach. Conclusion: QF-PCR can replace chromosomal analysis of CV-DIR in most cases during routine prenatal diagnosis, requiring smaller CV samples and being more labor effective. Coupled with LTC, it is a robust diagnostic approach with high predictive value for the most frequent fetal trisomies.

Double and multiple chromosomal aneuploidies in spontaneous abortions: A single institutional experience

“…These results clearly demonstrate the importance of using direct cultures instead using more expensive molecular techniques. [ 11 12 ] Our high abnormal rate may in part be due to fresh specimens we receive and as well as the use of direct culture.…”

Knowledge and Attitudes towards Prenatal Diagnostic Procedures among Pregnant Women in Greece

“…In the last decade, a first-trimester screening test based on sonographic and biochemical markers applied universally to all pregnant women has progressively gained ground over the second-trimester screening tests, which were based on the abnormal biochemistry at 16-20 weeks of gestation or were applied to high-risk pregnancies for aneuploidy due to advanced maternal age and/or the detection of sonographic markers at the ge- [22,23] . In addition, rapid testing and availability of the results within a day may have implications in the provided genetic counseling [24,25] . After these changes in the strategies regarding prenatal screening of the pregnant population as well as the influx of migrants in the country that has altered the homogeneity of the women of reproductive age in Greece, a study to examine trends in the current levels of women's knowledge and attitudes towards prenatal diagnostic examinations has been attempted with regard to demographic, lifestyle and medical history parameters.…”

Outcome of pregnancies with trisomy 2 cells in chorionic villi

“…At King's College Hospital, London, UK and Mitera Hospital, Athens, Greece CVS is carried out at 11-13 weeks for fetal karyotyping at the request of the parents after screening for trisomies either by maternal age or maternal age, fetal nuchal translucency thickness and maternal serum free β-hCG and PAPP-A (Kagan et al, 2008). In both centers, in the majority of samples a direct preparation was not performed because it was replaced by rapid analysis of the most frequent aneuploidies by quantitative fluorescence PCR (QF-PCR) (Christopoulou et al, 2009). Cytogenetic analysis of chorionic villi was performed by standard techniques which involve the setting up of two to three primary long-term cultures, metaphase chromosome preparations and analysis of 10-20 cells from two different cultures by GTG banding.…”