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

Abstract

Objective: We previously reported on the validation of Prenatal BACs-on-BeadsTM on retrospectively selected and prospective prenatal samples. This bead-based multiplex assay detects chromosome 13, 18, 21 and X/Y aneuploidies and the nine most frequent microdeletion syndromes. We demonstrated that Prenatal BACs-on-BeadsTM is a newgeneration, prenatal screening tool. Here, we describe the experience of five European prenatal diagnosis laboratories concerning the ongoing use of Prenatal BACs-on-BeadsTM. Methods Some 1653 samples were analyzed. All results were confirmed by conventional karyotyping or another appropriate technique. All indications for invasive prenatal diagnosis were included. Amniotic fluid and chorionic villus samples were analyzed in equivalent proportions. Results The failure rate was 3.3% and the overall abnormality detection rate was ~1/10. Eighty-five percent of the detected abnormalities were common aneuploidies. Eleven microdeletions and duplications were identified, thus giving an overall yield for microdeletion and microduplication detection of 1/145. Compared with QF-PCR, Prenatal BACs-on-BeadsTM provides an additional detection rate of ~1/250 for low-risk pregnancies. The false positive and negative rates were both <1%. Conclusion When associated with conventional karyotyping, the Prenatal BACs-on-BeadsTM 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. © 2012 John Wiley & Sons, Ltd

En este artículo validamos la técnica de diagnóstico genético BACs-on-Beads™ en muestras prenatales prospectivas y seleccionadas retrospectivamente. Este ensayo multiplex basado en bolitas con un marcaje fluorescente específico detecta aneuploidías de los cromosomas 13, 18, 21 y X/Y y los nueve síndromes de microdeleción más frecuentes. Demostramos que Prenatal BACs-on-Beads (TM) es una herramienta de detección prenatal de nueva generación. Aquí describimos la experiencia de cinco laboratorios europeos de diagnóstico prenatal con respecto al uso continuo de Prenatal BACs-on-Beads™. Se analizaron 1653 muestras de líquido amniótico y vellosidades coriónicas en proporciones equivalentes. Esta técnica permite obtener un resultado en un tiempo de respuesta muy corto (típico de las pruebas rápidas de detección de aneuploidías) con una importante información adicional detectando los síndromes de microdeleción más frecuentes que no pueden detectarse en los análisis citogenéticos convencionales.