Non-invasive cell-free DNA-based approach for the diagnosis of clinical miscarriage: A retrospective study.

Objective: To evaluate cell-free DNA (cfDNA) testing as a non-invasive approach to detecting aneuploidies in clinical miscarriages.

Design: A retrospective cohort study of women with pregnancy loss.

Setting: Hospitals and genetic analysis laboratories.

Inherited unbalanced reciprocal translocation with 3q duplication and 5p deletion in a foetus revealed by cell-free foetal DNA (cffDNA) testing: a case report.

Background: Since 2011, screening maternal blood for cell-free foetal DNA (cffDNA) fragments has offered a robust clinical tool to classify pregnancy as low or high-risk for Down, Edwards, and Patau syndromes. With recent advances in molecular biology and improvements in data analysis algorithms, the screening's scope of analysis continues to expand. Indeed, screening now encompassess additional conditions, including aneuploidies for sex chromosomes, microdeletions and microduplications, rare autosomal trisomies, and, more recently, segmental deletions and duplications called copy number variations (CNVs).

Characteristics of the IVF Cycle that Contribute to the Incidence of Mosaicism.

Highly sensitive next-generation sequencing (NGS) platforms applied to preimplantation genetic testing for aneuploidy (PGT-A) allow the classification of mosaicism in trophectoderm biopsies. However, the incidence of mosaicism reported by these tests can be affected by a wide number of analytical, biological, and clinical factors. With the use of a proprietary algorithm for automated diagnosis of aneuploidy and mosaicism, we retrospectively analyzed a large series of 115,368 trophectoderm biopsies from 27,436 PGT-A cycles to determine whether certain biological factors and fertilization (IVF) practices influence the incidence of overall aneuploidy, whole uniform aneuploidy, mosaicism, and TE biopsies with only segmental aneuploidy.

Clinical application of embryo aneuploidy testing by next-generation sequencing.

We review here the evolution in the field of embryo aneuploidy testing over the last 20 years, from the analysis of a subset of chromosomes by fluorescence in situ hybridisation to the transition toward a more comprehensive analysis of all 24 chromosomes. This current comprehensive aneuploidy testing most commonly employs next-generation sequencing (NGS). We present our experience in over 130 000 embryo biopsies using this technology.

Molecular analysis of products of conception obtained by hysteroembryoscopy from infertile couples.

Purpose: To analyze the molecular cytogenetic data obtained from products of conception (POC) obtained by selective biopsy of first trimester miscarriages and to estimate the rate of chromosomal anomalies in miscarriages from pregnancies achieved by natural conception (NC) or by assisted reproductive technology (ART) interventions.

Methods: We used KaryoLite™ BoBs™ (PerkinElmer LAS, Wallac, Turku, Finland) technology to analyze 189 samples from ART or NC pregnancies.

Results: All POC were successfully evaluated.

New tools for embryo selection: comprehensive chromosome screening by array comparative genomic hybridization.

The objective of this study was to evaluate the usefulness of comprehensive chromosome screening (CCS) using array comparative genomic hybridization (aCGH). The study included 1420 CCS cycles for recurrent miscarriage (n = 203); repetitive implantation failure (n = 188); severe male factor (n = 116); previous trisomic pregnancy (n = 33); and advanced maternal age (n = 880). CCS was performed in cycles with fresh oocytes and embryos (n = 774); mixed cycles with fresh and vitrified oocytes (n = 320); mixed cycles with fresh and vitrified day-2 embryos (n = 235); and mixed cycles with fresh and vitrified day-3 embryos (n = 91).

BACs-on-Beads technology: a reliable test for rapid detection of aneuploidies and microdeletions in prenatal diagnosis.

The risk of fetal aneuploidies is usually estimated based on high resolution ultrasound combined with biochemical determination of criterion in maternal blood, with invasive procedures offered to the population at risk. The purpose of this study was to investigate the effectiveness of a new rapid aneuploidy screening test on amniotic fluid (AF) or chorionic villus (CV) samples based on BACs-on-Beads (BoBs) technology and to compare the results with classical karyotyping by Giemsa banding (G-banding) of cultured cells in metaphase as the gold standard technique. The prenatal-BoBs kit was used to study aneuploidies involving chromosomes 13, 18, 21, X, and Y as well as nine microdeletion syndromes in 321 AF and 43 CV samples.

Use of array comparative genomic hybridization (array-CGH) for embryo assessment: clinical results.

Objective: To review clinical outcomes after preimplantation genetic screening. Most methods of embryo viability assessment involve morphologic evaluation at different preimplantation developmental stages. A weak association between blastocyst morphology and aneuploidy has been described, supporting the basis for preimplantation genetic screening (PGS) for assessment of embryo viability.