QF‐PCR as a substitute for karyotyping of cytotrophoblast for the analysis of chorionic villi: advantages and limitations from a cytogenetic retrospective audit of 44,727 first‐trimester prenatal diagnoses

Abstract

These results should be clearly highlighted in the pre-test counseling and extensively discussed with the couple prior to testing for informed consent.

Fetoplacental mosaicism: potential implications for false-positive and false-negative noninvasive prenatal screening results

“…14,15 In the direct preparation technique, metaphases were obtained "directly" from spontaneously dividing in vivo cytotrophoblasts using the protocol originally developed by Simoni et al in 1983. 16 Mesenchymal core analysis was performed on cultured cells, as previously described.…”

Comment on “QF‐PCR as a substitute for karyotyping of cytotrophoblast for the analysis of chorionic villi: advantages and limitations from a cytogenetic retrospective audit of 44 727 first‐trimester prenatal diagnoses”

“…We read with great interest the article by Grati et al, entitled 'QF-PCR as a substitute for karyotyping of cytotrophoblast for the analysis of chorionic villi: advantages and limitations from a cytogenetic retrospective audit of 44 727 first-trimester prenatal diagnoses'. 1 This article shows the considerable experience that this Italian team has in performing cytogenetic tests on chorionic villus samplings (CVS) and in particular, based on a retrospective study of more than 44 000 firsttrimester trophoblast biopsies, demonstrates the`need to challenge the gold standard for cytogenetic testing carried out on these samples [short-term culture (STC) + long-term culture (LTC)], a gold standard set over 20 years ago. 2 In our fetal medicine center, we have performed more than 28 000 early and late CVS since 1983, in all pregnancy trimesters, and like our Italian colleagues, we are constantly trying to improve the cytogenetic techniques applied to chorionic villi, the aim being to obtain notably a rapid and reliable cytogenetic result before 14 weeks of amenorrhea.…”

Assessing the cost of implementing the 2011 Society of Obstetricians and Gynecologists of Canada and Canadian College of Medical Genetics practice guidelines on the detection of fetal aneuploidies

“…The stated benefits of the 2011 SOGC–CCMG guidelines are as follows: to provide rapid and accurate results for pregnancies at risk for a common aneuploidy, promote better use of laboratory resources and reduce the cost of prenatal diagnosis . A number of studies have assessed the accuracy and rapidity of QF‐PCR testing in this setting showing that only a small percent of abnormal cases would be missed by replacing karyotype with QF‐PCR for pregnancies at increased risk for a common aneuploidy . Pre‐test genetic counselling is important to help patients understand the limitations of QF‐PCR.…”