GARS-related disease in infantile spinal muscular atrophy: Implications for diagnosis and treatment.

The majority of patients with spinal muscular atrophy (SMA) identified to date harbor a biallelic exonic deletion of SMN1. However, there have been reports of SMA-like disorders that are independent of SMN1, including those due to pathogenic variants in the glycyl-tRNA synthetase gene (GARS1). We report three unrelated patients with de novo variants in GARS1 that are associated with infantile-onset SMA (iSMA). Patients were ascertained during inpatient hospital evaluations for complications of neuropathy. Evaluations were completed as indicated for clinical care and management and informed consent for publication was obtained. One newly identified, disease-associated GARS1 variant, identified in two out of three patients, was analyzed by functional studies in yeast complementation assays. Genomic analyses by exome and/or gene panel and SMN1 copy number analysis of three patients identified two previously undescribed de novo missense variants in GARS1 and excluded SMN1 as the causative gene. Functional studies in yeast revealed that one of the de novo GARS1 variants results in a loss-of-function effect, consistent with other pathogenic GARS1 alleles. In sum, the patients' clinical presentation, assessments of previously identified GARS1 variants and functional assays in yeast suggest that the GARS1 variants described here cause iSMA. GARS1 variants have been previously associated with Charcot-Marie-Tooth disease (CMT2D) and distal SMA type V (dSMAV). Our findings expand the allelic heterogeneity of GARS-associated disease and support that severe early-onset SMA can be caused by variants in this gene. Distinguishing the SMA phenotype caused by SMN1 variants from that due to pathogenic variants in other genes such as GARS1 significantly alters approaches to treatment.

Loss of function in ROBO1 is associated with tetralogy of Fallot and septal defects.

BACKGROUND: Congenital heart disease (CHD) is a common birth defect affecting approximately 1% of newborns. Great progress has been made in elucidating the genetic aetiology of CHD with advances in genomic technology, which we leveraged in recovering a new pathway affecting heart development in humans previously known to affect heart development in an animal model. METHODS: Four hundred and sixteen individuals from Thailand and the USA diagnosed with CHD and/or congenital diaphragmatic hernia were evaluated with chromosomal microarray and whole exome sequencing. The DECIPHER Consortium and medical literature were searched for additional patients. Murine hearts from ENU-induced mouse mutants and transgenic mice were evaluated using both episcopic confocal histopathology and troponin I stained sections. RESULTS: Loss of function ROBO1 variants were identified in three families; each proband had a ventricular septal defect, and one proband had tetralogy of Fallot. Additionally, a microdeletion in an individual with CHD was found in the medical literature. Mouse models showed perturbation of the Slit-Robo signalling pathway, causing septation and outflow tract defects and craniofacial anomalies. Two probands had variable facial features consistent with the mouse model. CONCLUSION: Our findings identify Slit-Robo as a significant pathway in human heart development and CHD.

The Bacterial iprA Gene Is Conserved across Enterobacteriaceae, Is Involved in Oxidative Stress Resistance, and Influences Gene Expression in Salmonella enterica Serovar Typhimurium.

UNLABELLED: The iprA gene (formerly known as yaiV or STM0374) is located in a two-gene operon in the Salmonella enterica serovar Typhimurium genome and is associated with altered expression during spaceflight and rotating-wall-vessel culture conditions that increase virulence. However, iprA is uncharacterized in the literature. In this report, we present the first targeted characterization of this gene, which revealed that iprA is highly conserved across Enterobacteriaceae We found that S Typhimurium, Escherichia coli, and Enterobacter cloacae ΔiprA mutant strains display a multi-log-fold increase in oxidative stress resistance that is complemented using a plasmid-borne wild-type (WT) copy of the S Typhimurium iprA gene. This observation was also associated with increased catalase activity, increased S Typhimurium survival in macrophages, and partial dependence on the katE gene and full dependence on the rpoS gene. Our results indicate that IprA protein activity is sensitive to deletion of the N- and C-terminal 10 amino acids, while a region that includes amino acids 56 to 80 is dispensable for activity. RNA sequencing (RNA-Seq) analysis revealed several genes altered in expression in the S Typhimurium ΔiprA mutant strain compared to the WT, including those involved in fimbria formation, spvABCD-mediated virulence, ethanolamine utilization, the phosphotransferase system (PTS) transport, and flagellin phase switching from FlgB to FliC (likely a stochastic event) and several genes of hypothetical or putative function. IMPORTANCE: Overall, this work reveals that the conserved iprA gene measurably influences bacterial biology and highlights the pool of currently uncharacterized genes that are conserved across bacterial genomes. These genes represent potentially useful targets for bacterial engineering, vaccine design, and other possible applications.

Characterization of the Salmonella enterica serovar Typhimurium ydcI gene, which encodes a conserved DNA binding protein required for full acid stress resistance.

Salmonella enterica serovar Typhimurium possesses a stimulon of genes that are differentially regulated in response to conditions of low fluid shear force that increase bacterial virulence and alter other phenotypes. In this study, we show that a previously uncharacterized member of this stimulon, ydcI or STM1625, encodes a highly conserved DNA binding protein with related homologs present in a range of gram-negative bacterial genera. Gene expression analysis shows that ydcI is expressed in different bacterial genera and is involved in its autoregulation in S. Typhimurium. We demonstrate that purified YdcI protein specifically binds a DNA probe consisting of its own promoter sequence. We constructed an S. Typhimurium ΔydcI mutant strain and show that this strain is more sensitive to both organic and inorganic acid stress than is an isogenic WT strain, and this defect is complemented in trans. Moreover, our data indicate that ydcI is part of the rpoS regulon related to stress resistance. The S. Typhimurium ΔydcI mutant was able to invade cultured cells to the same degree as the WT strain, but a strain in which ydcI expression is induced invaded cells at a level 2.8 times higher than that of the WT. In addition, induction of ydcI expression in S. Typhimurium resulted in the formation of a biofilm in stationary-phase cultures. These data indicate the ydcI gene encodes a conserved DNA binding protein involved with aspects of prokaryotic biology related to stress resistance and possibly virulence.

A patient with atypical presentation of chronic hepatosteatosis harboring a novel variant in the CPT1A gene.

Carnitine palmitoyltransferase 1A (CPT1A) deficiency is a rare disorder of hepatic long-chain fatty acid oxidation. Most patients with CPT1A deficiency present with hypoketotic hypoglycemia and hepatic encephalopathy. We describe an atypical case of an 8-year-old male with CPT1A deficiency presenting with chronic liver steatosis and cirrhosis. He also had a history of developmental delay, autism spectrum disorder, and mild dysmorphic features of unknown cause. His newborn screening test suggested CPT1A deficiency, but confirmatory biochemical testing was not conclusive. The patient never experienced a metabolic crisis. At age six, hepatomegaly was detected. Further investigations showed transaminitis, hepatosteatosis and cirrhosis. Repeat acylcarnitine profile and total/free carnitine were consistent with CPT1A deficiency. The CPTI enzyme activity was 18% of normal on fibroblast enzyme assay. A novel homozygous variant in the CPT1A gene, c.1394G > A (p.Gly465Glu) was identified from whole-exome sequencing. To our knowledge, the patient is the first reported individual with CPT1A deficiency and chronic liver steatosis and fibrosis. Developmental delay and autistic spectrum disorder are not typical features of CPT1A deficiency, given that the patient never experienced any metabolic decompensation.

Missense variant contribution to USP9X-female syndrome.

USP9X is an X-chromosome gene that escapes X-inactivation. Loss or compromised function of USP9X leads to neurodevelopmental disorders in males and females. While males are impacted primarily by hemizygous partial loss-of-function missense variants, in females de novo heterozygous complete loss-of-function mutations predominate, and give rise to the clinically recognisable USP9X-female syndrome. Here we provide evidence of the contribution of USP9X missense and small in-frame deletion variants in USP9X-female syndrome also. We scrutinise the pathogenicity of eleven such variants, ten of which were novel. Combined application of variant prediction algorithms, protein structure modelling, and assessment under clinically relevant guidelines universally support their pathogenicity. The core phenotype of this cohort overlapped with previous descriptions of USP9X-female syndrome, but exposed heightened variability. Aggregate phenotypic information of 35 currently known females with predicted pathogenic variation in USP9X reaffirms the clinically recognisable USP9X-female syndrome, and highlights major differences when compared to USP9X-male associated neurodevelopmental disorders.

Bringing "The Real Cost" to Life Through Breakthrough, Evidence-Based Advertising.

Building on the success "The Real Cost" campaign has already achieved requires the constant development of new audience insights, novel ideas, and unconventional ways of bringing the campaign to life. This article provides a high-level overview of the campaign's approach to developing and testing breakthrough advertising that has proven effective in preventing smoking initiation among a skeptical, hard-to-reach, at-risk youth audience. This approach is informed by evidence-based communication best practices for youth behavior change campaigns; insights from published literature and subject matter experts with decades of experience in youth health marketing and tobacco prevention; and findings from formative research studies conducted as part of the campaign development process. The paper also explores two campaign advertisements to showcase the research-based creative development process in action. This article is a collaboration between federal government officials, campaign managers, ad agency creatives, and researchers, and thus provides a unique, multidisciplinary examination into the research and creative processes that go into creating a national health communication effort. SUPPLEMENT INFORMATION: This article is part of a supplement entitled Fifth Anniversary Retrospective of "The Real Cost," the Food and Drug Administration's Historic Youth Smoking Prevention Media Campaign, which is sponsored by the U.S. Food and Drug Administration.