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Numerous studies have shown evidence supporting the benefits of universal newborn screening for primary immunodeficiencies (PID) and for Spinal Muscular Atrophy (SMA). We have developed a four-plex, real-time PCR assay to screen for Severe Combined Immune Deficiencies (SCID), X-linked agammaglobulinemia (XLA), and SMA in DNA extracted from a single 3.2 mm punch of a dried blood spot (DBS). A simple, high-throughput, semi-automated DNA extraction method was developed for a Janus liquid handler that can process 384 DBS punches in four 96-well plates in just over one hour with sample tracking capability. The PCR assay identifies the absence of exon 7 in the SMN1 gene, while simultaneously evaluating the copy number of T-cell receptor excision circles (TREC) and Kappa-deleting recombination excision circles (KREC) molecules. Additionally, the amplification of a reference gene, RPP30 , was included in the assay as a quality/quantity indicator of DNA isolated from the DBS. The assay performance was demonstrated on over 3000 DNA samples isolated from punches of putative normal newborn DBS. The reliability and analytical accuracy were further evaluated using DBS controls, and contrived and confirmed positive samples. The results from this study demonstrate the potential of future molecular DBS assays, and highlight how a multiplex assay could benefit newborn screening programs., Competing Interests: Conflicts of InterestC.G-M., A.T., K.V., M.J., G.F., S.D., D.G., D.S. and R.W. are PerkinElmer employees. Authors representing PerkinElmer had a role in designing the study, in collection, analyses, and interpretation of the data, in the writing of the manuscript, and in the decision to publish the results. The other authors declare no conflict of interest., (© 2019 by the authors.)

Different national and international agencies have selected specific STR sets for forensic database use. To enhance database comparison across national and international borders, a 27-locus multiplex system was developed comprising all 15 STR loci of the European standard set, the current 13 STR loci of the CODIS core, the proposed 22 STR loci of the expanded CODIS core, 4 additional commonly used STR loci, and the amelogenin locus. Development required iterative primer design to resolve primer-related artifacts, amplicon sizing, and locus-to-locus balance issues. The 19.5-min assay incorporated newly developed six-dye chemistry analyzed using a novel microfluidic electrophoresis instrument capable of simultaneous detection and discrimination of 8 or more fluorescent dyes. The 27-locus multiplex offers the potential for a new international STR standard permitting laboratories in any jurisdiction to use a single reaction to determine profiles for loci they typically generate plus an expanded common STR profiling set of global interest., (© 2013 American Academy of Forensic Sciences.)

Objective: To identify and transfer cytogenetically normal embryos after screening all chromosomes of first and second polar bodies (PBs) or trophectoderm samples with the use of comparative genomic hybridization., Design: Clinical research study., Setting: In vitro fertilization clinic referring samples to a specialist preimplantation genetic diagnosis laboratory., Patient(s): Thirty-two couples with repeated implantation failure., Intervention(s): Zygotes from patients with repeated implantation failure and poor response to ovarian stimulation underwent PB biopsy. Patients with repeated implantation failure who were candidates for blastocyst transfer received trophectoderm biopsy. Zygotes or blastocysts were vitrified while chromosome analysis took place. Euploid embryos were transferred during a subsequent cycle., Main Outcome Measure(s): Cytogenetic status and implantation and pregnancy rates., Result(s): The oocyte and blastocyst aneuploidy rates were 65.5% and 45.2%, respectively. Abnormalities affecting all chromosomes were detected. Implantation and pregnancy rates for the patients with PB biopsy were 11.5% and 21.4%, respectively, whereas for patients receiving blastocyst analysis they were 58.3% and 69.2%., Conclusion(s): Initial results for patients of advanced maternal age (39.8 years) with repeated implantation failure and poor ovarian response were encouraging. However, further study is required to confirm whether or not screening is beneficial. Blastocyst analysis was associated with high pregnancy rates, suggesting that comprehensive chromosome screening may assist patients with repeated implantation failure capable of producing blastocysts in achieving pregnancies., (Copyright (c) 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)