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Abstract Background GATA1-related cytopenia (GRC) is characterized by thrombocytopaenia and/or anaemia ranging from mild to severe. Haematopoietic stem cell transplantation (HSCT) is a healing therapeutic choice for GRC patients. We identified a novel pathogenic variant (GATA1: c.1019delG) in a boy with GATA1-related cytopenia. Then we performed preimplantation genetic testing (PGT) in this GRC family. After a mosaic embryo transfered, a healthy and HLA-compatible with the proband baby was delivered. Case presentation The proband is a 6-year-old boy who was diagnosed to have transfusion-dependent anaemia since 3 year old. Whole-exome sequencing (WES) showed that the proband has a hemizygous variant c.1019delG in GATA1, which is inherited from his mother. His parents decided to undergo PGT to have a health and HLA-compatible offspring. After whole genome amplification (WGA) of biopsied trophectoderm (TE) cells, next generation sequencing (NGS)-based PGT was preformed to analyse embryos on chromosomal aneuploidy, target mutation and HLA typing. There were 3 embryos HLA-matched to the proband. The genotypes of the 3 embryos were heterozygous variant, hemizygous variant, normal respectively. After a heterozygous, mosaic partial trisomy (chr)16, and HLA-matched embryo transfer, a healthy baby was delivered and whose HSCT is compatible with the proband. Conclusions NGS-based PGT-HLA is a valuable procedure for the treatment of GATA1-related cytopenia caused by GATA1 variants, or other haematological disorders, oncological and immunological diseases. Furthermore, our study reconfirms that mosaic embryos transfer would bring healthy offspring.

With the development of high-throughput sequencing, the genetic etiology of many diseases has been revealed. However, this has also led to the categorization of many variants as variants of uncertain significance (VUSs), presenting a major challenge in genetic counseling. A couple with a history of adverse pregnancies sought assisted reproductive technology. Trio-WES revealed that they individually carried the following variants in the RPGRIP1L gene: a c.1581G>A (p.Gln527=) (VUS) and a c.135-11A>G (likely pathogenic variant, LP). Further investigation using the Minigene assay showed that the variant c.1581G>A (p.Gln527=) disrupts the normal splicing pattern of the mRNA, leading to two abnormal splicing modes: 1) retention of 26 bp in intron 13; 2) exon 13 skipping transcript. Consequently, the VUS was reclassified as likely pathogenic. We then performed preimplantation genetic testing (PGT) for the couple, which included direct detection of the RPGRIP1L locus, SNP haplotype analysis, and chromosome copy number detection. Through these precise detection procedures, an unaffected embryo was selected for transfer, and the prenatal genetic diagnosis of the fetus was normal. Our study indicates that the Minigene assay is a valuable tool for splicing functional analysis of variants in vitro. This approach is particularly useful for genetic counseling involving VUS that may affect pre-mRNA splicing, as well as for the subsequent clinical management of the related family.

Abstract In early type 2 diabetes, the strategy of “induction” with short-term intensive insulin therapy followed by “maintenance” with metformin can stabilize pancreatic beta-cell function in some patients but not others. We thus sought to elucidate determinants of sustained stabilization of beta-cell function. In this secondary analysis of ClinicalTrials.Gov NCT02192424, adults with ≤5-years diabetes duration were randomized to 3-weeks induction insulin therapy (glargine/lispro) followed by metformin maintenance either with or without intermittent 2-week courses of insulin every 3-months for 2-years. Sustained stabilization (higher beta-cell function at 2-years than at baseline) was achieved in 55 of 99 participants. Independent predictors of sustained stabilization were the change in beta-cell function during induction and changes in hepatic insulin resistance and alanine aminotransferase during maintenance. Thus, initial reversibility of beta-cell dysfunction during induction and subsequent preservation of hepatic insulin sensitivity during maintenance are associated with sustained stabilization of beta-cell function following short-term insulin and metformin. ClinicalTrials.Gov NCT02192424

Abstract Background Aicardi–Goutières syndrome (AGS) is a rare, autosomal recessive, hereditary neurodegenerative disorder. It is characterized mainly by early onset progressive encephalopathy, concomitant with an increase in interferon-α levels in the cerebrospinal fluid. Preimplantation genetic testing (PGT) is a procedure that could be used to choose unaffected embryos for transfer after analysis of biopsied cells, which prevents at-risk couples from facing the risk of pregnancy termination. Methods Trio-based whole exome sequencing, karyotyping and chromosomal microarray analysis were used to determine the pathogenic mutations for the family. To block the inheritance of the disease, multiple annealing and looping-based amplification cycles was used for whole genome amplification of the biopsied trophectoderm cells. Sanger sequencing and next-generation sequencing (NGS)-based single nucleotide polymorphism (SNP) haplotyping were used to detect the state of the gene mutations. Copy number variation (CNV) analysis was also carried out to prevent embryonic chromosomal abnormalities. Prenatal diagnosis was preformed to verify the PGT outcomes. Results A novel compound heterozygous mutation in TREX1 gene was found in the proband causing AGS. A total of 3 blastocysts formed after intracytoplasmic sperm injection were biopsied. After genetic analyses, an embryo harbored a heterozygous mutation in TREX1 and without CNV was transferred. A healthy baby was born at 38th weeks and prenatal diagnosis results confirmed the accuracy of PGT. Conclusions In this study, we identified two novel pathogenic mutations in TREX1, which has not been previously reported. Our study extends the mutation spectrum of TREX1 gene and contributes to the molecular diagnosis as well as genetic counseling for AGS. Our results demonstrated that combining NGS-based SNP haplotyping for PGT-M with invasive prenatal diagnosis is an effective approach to block the transmission of AGS and could be applied to prevent other monogenic diseases.

Summary: Background: The cardiometabolic implications of postprandial hyperinsulinemia are unclear with recent studies suggesting both adverse and beneficial associations. We aimed to evaluate the longitudinal cardiometabolic implications of the post–challenge insulin secretory response over 4-years follow-up. Methods: In this prospective cohort study, conducted in Toronto (Ontario, Canada), women comprising the full range of antepartum glucose tolerance were recruited in pregnancy (at the time of glucose tolerance screening, late in the second trimester) to undergo cardiometabolic testing in the years thereafter. Participants underwent oral glucose tolerance tests (OGTT) at 1-year, 3-years, and 5-years postpartum, enabling serial assessment of cardiovascular risk factors, glucose tolerance, insulin sensitivity or resistance (Matsuda index, HOMA-IR), and beta-cell function—via Insulin Secretion-Sensitivity Index-2 (ISSI-2) and insulinogenic index/HOMA-IR (IGI/HOMA-IR). Baseline post–challenge insulinemia was assessed with the corrected insulin response (CIR) at 1-year. Cardiometabolic factors were compared between baseline CIR tertiles. Findings: Between Oct 23, 2003 and March 31, 2014, 306 women were enrolled. In this study population, there was progressive worsening of waist circumference (p = 0.016), HDL (p = 0.018), CRP (p = 0.006), and insulin sensitivity (p

Abstract Objective Basal insulin glargine has a neutral effect on cardiovascular risk in type 2 diabetes (T2DM). In practice, basal insulin is often paired with a glucagon-like peptide-1 receptor agonist (GLP1-RA) or meal insulin; however, the cardiovascular implications of these combinations have not been fully elucidated. In this context, we sought to evaluate the vascular function effects of adding the GLP1-RA exenatide or meal insulin lispro to basal glargine therapy in early T2DM. Methods In this 20-week trial, adults with T2DM of

Abstract Pathogenic dental plaque biofilms are universal and harmful, which can result in oral infections and systemic diseases. Many conventional therapeutic methods have proven insufficient or ineffective against plaque biofilms. Therefore, new strategies are urgently needed. Fusobacterium nucleatum (F. nucleatum), a periodontal pathogen associated with a variety of oral and systemic diseases, is thought to be central to the development and structure of dental plaques. Here, ultra-small gold nanoclusters (AuNCs) were prepared. They exhibited potent antibacterial activity against F. nucleatum through enhanced destruction of bacterial membranes and generation of reactive oxygen species. Furthermore, due to their excellent penetration, the AuNCs could inhibit biofilm formation and destroy mature biofilms in vitro. Their antibiofilm efficacy was further confirmed in a mouse model, where they reduced biofilm accumulation and ameliorated inflammation. Meanwhile, the disruption of oral and gut microbiota caused by colonization of oral F. nucleatum could be partially restored through AuNCs treatment. Therefore, AuNCs could be considered as promising antibiofilm agents and have great potential in the clinical treatment of dental plaque. Graphical Abstract