Prenatal BACs‐on‐Beads^TM: the prospective experience of five prenatal diagnosis laboratories

Abstract

When associated with conventional karyotyping, the Prenatal BACs-on-Beads™ assay combines a short turnaround time (typical of rapid aneuploidy detection tests) with valuable detection of the most frequent microdeletion syndromes that cannot be detected in cytogenetic analyses.

Prenatal BoBsTM in the cytogenetic analysis of products of spontaneous miscarriage

“…Eight cases were uninterpretable, giving a technical failure rate of 11.4%, which was higher than the rate of ~3% registered for prenatal screening using Prenatal BoBs TM [5,12] and also higher than the rate of ~ 2% reported for the screening of POCs using Karyolite Bobs TM . [6,10] These results may be explained by the fact that we had numerous samples with poor DNA quality due to advanced maceration of fetal tissue.…”

“…This rapid targeted assay is dependent on DNA extraction and does not require live or intact cells, and represents an interesting alternative to conventional cytogenetics that require cell culture. [5,9,11,12] In our study, cell culture failure prevented standard karyotype analysis of 38 samples. However, Prenatal BoBs TM provided a conclusive result in all cases, making it a useful tool for the cytogenetic analysis of POCs, especially when culture fails.…”

“…Two assays are available, Prenatal BoBs TM for the detection of trisomy 13, 18, and 21 and the most frequent syndromes associated with microdeletions, and KaryoLite BoBs TM , which can detect aneuploidy in all chromosomes by quantifying the proximal and terminal regions of each chromosome arm. Prenatal BoBs TM has been shown to be a robust technology for the prenatal investigation of fetuses with or without abnormalities on ultrasound, [5,9] whereas KaryoLite BoBs TM has been found clinically useful for the investigation of SM products. [10] Since September 2012, Prenatal BoBs TM has been used for prenatal diagnosis in the routine clinical setting in the Medical Cytogenetic Service of the University Hospital of Clermont-Ferrand (France).…”

“…[5][6][7] Performed within 24 -48 hours, as opposed to weeks for karyotyping, these do not require cell culture, and DNA can be analysed directly after it is extracted. However, while it is possible to investigate several regions with FISH, the number of regions that can be explored with QF-PCR is limited, and MLPA requires the use of two commercial kits to invesigate subtelomere regions.…”

Bacterial artificial chromosomes (BACs)-on-Beads™ as a diagnostic platform for the rapid aneuploidy screening of products of conception

“…Cytogenetic techniques that are not dependent on actively growing tissue are becoming more common, including quantitative fluorescence (QF)-PCR (2,3), multiplex ligation-dependent probe amplification (MLPA) (4,5), molecular karyotyping (6) and bacterial artificial chromosomes (BACs)-on-Beads™ (BoBs) (7)(8)(9)(10)(11). Of these techniques, BoBs offers the ability to assess small batch sizes at a relatively low cost with comprehensive coverage of all the chromosome arms, whilst complementing the highly interrogative array-based methods that are used in molecular karyotyping.…”