Generation of Nonmosaic, Two-Pore Channel 2 Biallelic Knockout Pigs in One Generation by CRISPR-Cas9 Microinjection Before Oocyte Insemination. | LitMetric
Department of Physiology, Faculty of Veterinary, University of Murcia, Campus Mare Nostrum, Murcia, Spain.
Published: February 2021
AI Article Synopsis
Article Abstract
Studies of knockout (KO) mice with defects in the endolysosomal two-pore channels (TPCs) have shown TPCs to be involved in pathophysiological processes, including heart and muscle function, metabolism, immunity, cancer, and viral infection. With the objective of studying TPC2's pathophysiological roles for the first time in a large, more humanlike animal model, TPC2 KO pigs were produced using CRISPR-Cas9. A major problem using CRISPR-Cas9 to edit embryos is mosaicism; thus, we studied for the first time the effect of microinjection timing on mosaicism. Mosaicism was greatly reduced when produced embryos were microinjected before insemination, and surgical embryo transfer (ET) was performed using such embryos. All TPC2 KO fetuses and piglets born following ET (i.e., F0 generation) were nonmosaic biallelic KOs. The generation of nonmosaic animals greatly facilitates germ line transmission of the mutation, thereby aiding the rapid and efficient generation of KO animal lines for medical research and agriculture.
The emergence of the FC428 clone of Neisseria gonorrhoeae (Ng) has led to concerns about antimicrobial resistance, with ceftriaxone being the last remaining effective treatment option due to the development of high-level resistance associated with a newly identified allele.
Analysis of 2,104 genomes showed that three isolates with high-level ceftriaxone resistance grouped in a lineage that includes strains primarily from North America and Southeast Asia, indicating significant global spread and interconnectedness of resistant strains.
The study identifies potential recombination events that could contribute to the evolution of resistant strains, highlighting the complex nature of antimicrobial resistance and the need for ongoing surveillance and research.
Mosaic Down syndrome involves a partial triplication of chromosome 21 found in some cells and is less understood epidemiologically; a study analyzed its prevalence among 94,533 Medicaid adults from 2016 to 2019.
The research identified 1,966 individuals with mosaic Down syndrome, finding no significant differences in prevalence by sex or race/ethnicity, but noted higher rates of autism and ADHD in this group compared to those with nonmosaic Down syndrome.
The study suggests that mosaicism might increase the risk for certain neurodevelopmental and neurodegenerative disorders, particularly Alzheimer's dementia, indicating a need for further research to understand these correlations better.
Preimplantation genetic testing for aneuploidies (PGT-A) is commonly used in assisted reproduction, but surprisingly, it doesn't significantly enhance clinical outcomes due to discrepancies between PGT-A results and the actual chromosomal makeup of blastocysts.
A study analyzed 23 blastocysts from 17 couples, where PGT-A revealed chromosomal imbalances, by re-biopsying the trophectoderm (TE) and separately examining the inner cell mass (ICM).
Out of the 23 cases, only 8 had consistent PGT-A results with re-biopsy findings, while 4 showed partial discordance, indicating the complexity of accurately assessing chromosomal status in embryos.
Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania. Electronic address:
Inherited bone marrow failure syndromes (IBMFS) are a group of heterogeneous disorders that account for ∼30% of pediatric cases of bone marrow failure and are often associated with developmental abnormalities and cancer predisposition. This article reports the laboratory validation and clinical utility of a large-scale, custom-designed next-generation sequencing panel, Children's Hospital of Philadelphia (CHOP) IBMFS panel, for the diagnosis of IBMFS in a cohort of pediatric patients. This panel demonstrated excellent analytic accuracy, with 100% sensitivity, ≥99.
