title: Prenatal BoBsTM in the cytogenetic analysis of products of spontaneous miscarriage.
abstract: BACKGROUND
  Fifty percent of spontaneous miscarriages (SMs) are attributed to chromosomal abnormalities. Cytogenetic analysis is an important tool for patient counselling and assessment of the risk of recurrence in future pregnancies. Conventional karyotyping has been the gold standard for chromosomal investigation of products of conception (POC), but it has limitations due to sample maceration, culture failure and maternal cell contamination. Molecular cytogenetic approaches have therefore been developed and found valuable in the cytogenetic investigation of these samples. The Prenatal BoBsTM and KaryoLite BoBsTM, based on the newly developed BACs-on-BeadsTM technology, have been described as reliable tests for rapid detection of aneuploidies in prenatal and POC samples, respectively.
  
  
  OBJECTIVE
  To describe our clinical experience of routine screening of POC samples with Prenatal BoBsTM, the test used by our laboratory in France.
  
  
  METHODS
  Seventeen samples collected at the University Hospital of Sidi Bel Abbès (Western Algeria) and a further 60 from the University Hospital of Clermont-Ferrand (France) were analysed (19 chorionic villi from products of curettage, 12 placentas, 9 amniotic cells and 37 biopsy specimens). All were screened for the frequent aneuploidies (chromosomes 13, 18, 21, X and Y) in addition to nine microdeletion/microduplication syndrome regions by Prenatal BoBsTM. Standard karyotyping was performed on 51 samples, but failed in 38 cases.
  
  
  RESULTS
  Prenatal BoBsTM identified one trisomy 21 and one deletion of 17p13.3. Furthermore, it provided a conclusive result in cases of culture failure (n=38) and in samples with macerated tissue (n=19). The overall failure rate was 11.4%.
  
  
  CONCLUSIONS
  Prenatal BoBsTM is a promising technology that represents a fast, sensitive and robust alternative to routine screening for chromosomal abnormality in products of SM. Furthermore, it overcomes the limitations of conventional karyotyping and current molecular cytogenetic techniques.
authors.affiliation: Laboratoire de biotoxicologie, Department of Biology, Djillali Liabes University, Algeria; Faculty of Life and Natural Science, Department of Biology, Djillali Liabes University of Sidi Bel Abbès, Algeria. sara.mellali@yahoo.fr.
authors.forename: Sarah
authors.initials: S
authors.lastname: Mellali
authors.forename: Khadidja
authors.initials: K
authors.lastname: Haoud
authors.forename: Laetitia
authors.initials: L
authors.lastname: Gouas
authors.forename: Meghit Boumediene
authors.initials: MB
authors.lastname: Khaled
authors.forename: Philippe
authors.initials: P
authors.lastname: Vago
authors.forename: Soraya
authors.initials: S
authors.lastname: Moulessehoul