StabilitySort: assessment of protein stability changes on a genome-wide scale to prioritize potentially pathogenic genetic variation.

SUMMARY: Missense mutations that change protein stability are strongly associated with human genetic disease. With the recent availability of predicted structures for all human proteins generated using the AlphaFold2 prediction model, genome-wide assessment of the stability effects of genetic variation can, for the first time, be easily performed. This facilitates the interrogation of personal genetic variation for potentially pathogenic effects through the application of stability metrics. Here, we present a novel tool to prioritize variants predicted to cause strong instability in essential proteins. We show that by filtering by ΔΔG values and then prioritizing by StabilitySort Z-scores, we are able to more accurately discriminate pathogenic, protein-destabilizing mutations from population variation, compared with other mutation effect predictors. AVAILABILITY AND IMPLEMENTATION: StabilitySort is available as a web service (https://www.stabilitysort.org), as a data download for integration with other tools (https://www.stabilitysort.org/download) or can be deployed as a standalone system from source code (https://gitlab.com/baaron/StabilitySort). SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Expanding the clinical spectrum of pathogenic variation in NR2F2: Asplenia.

We present a case with congenital syndromic asplenia associated with immune deficiency, glandular hypospadias and cryptorchidism. Genetic analysis identified a likely pathogenic de novo variant in NR2F2. Pathogenic NR2F2 variants have been associated with other congenital anomalies affecting the central axis, such as congenital heart disease and diaphragmatic hernia, which were not part of our patient's clinical features. The association between NR2F2 and asplenia (including glandular hypospadias and cryptorchidism) has been described in animal models and our report is the first expanding the NR2F2 clinical spectrum in humans to include asplenia.

Implementation of an adult code sepsis protocol and its impact on SEP-1 core measure perfect score attainment in the ED.

INTRODUCTION: Timely management of sepsis has become an urgent concern among most hospitals. Institutions have been searching for unique ways to increase the quality of care and timely adherence to proven therapies. The objective of this study was to determine the impact of an Adult Code Sepsis Protocol on the rate of SEP-1 perfect score attainment (PSA) among patients who presented to the emergency department (ED) with severe sepsis or septic shock, as defined by the Centers for Medicare and Medicaid Services (CMS). METHODS: This was a retrospective, observational cohort study in a 35-bed tertiary care hospital ED from December 2016 to February 2018. Adults (≥18 years of age) who met the CMS-case definition of severe sepsis or septic shock presenting to the ED either prior to or after implementation of an Adult Code Sepsis Protocol were included. RESULTS: The primary outcome of SEP-1 PSA, which was abstracted in an all-or-none fashion, increased from 30.7% to 71.3% (p < 0.001). Inpatient mortality was reduced from 4% to 0% (p = 0.011) after protocol implementation. Protocol initiation also resulted in a significant reduction in both time to initiation of appropriate, empiric and effective antimicrobial therapy, based on culture results by 48 and 111 min, respectively (p < 0.001). There were no significant differences in other secondary outcomes including ICU length-of-stay, readmission, or economic outcome measures. CONCLUSIONS: The addition of an Adult Code Sepsis Protocol in the ED significantly increased the rate of SEP-1 PSA, reduced inpatient mortality, and improved the time to initiation of effective antimicrobial therapy.

Genomic test ends a long diagnostic odyssey in a patient with resistance to thyroid hormones.

BACKGROUND: Resistance to thyroid hormones is a very rare condition, which is often misdiagnosed and mistreated. The cases where there is a concomitant autoimmune thyroid disorder are ultra-rare and particularly challenging to treat. Diagnostic and research-based genomic testing can sometimes identify pathogenic variants unrelated to the primary reason for testing (incidental findings). CASE PRESENTATION: We present a patient with thyroid resistance associated with hypothyroid Hashimoto thyroiditis. The long diagnostic odyssey spanning over 20-years included repeated misdiagnoses and mistreatments and was concluded by a research-based genomic testing, identifying a "de novo" THRB pathogenic variant. The varying sensitivity of various tissues to thyroid hormones accompanied by hypothyroid Hashimoto thyroiditis continues to pose a significant treatment challenge. CONCLUSIONS: Thyroid hormone resistance continues to be an un(der)- and misdiagnosed thyroid condition whose management is particularly challenging when associated with autoimmune thyroid disease. Whole exome sequencing has the potential to identify THRB pathogenic variants as incidental findings. Reporting such secondary findings from genomic testing may be particularly important in the context of the rarity of the condition and the potential clinical consequences of misdiagnosis and mistreatment.

Systemic lupus erythematosus: A new autoimmune disorder in Kabuki syndrome.

We report a case of a 17-year-old Caucasian girl with syndromic features of clinically unrecognized Kabuki syndrome (KS), who developed systemic lupus erythematosus (SLE). Diagnosis of KS was established after whole exome sequencing (WES) and detection of de novo frameshift 1bp deletion in histone-lysine N-methyltransferase 2D gene (KMT2D). The pathogenic variant in exon 34 (c.8626delC: 55 reads C, 56 reads delC), has not been described previously and is predicted to truncate the protein (p.Gln2876Serfs*34) resulting in KMT2D loss of function. Notwithstanding that patients with KS have a substantial susceptibility to various autoimmune diseases, to the best of our knowledge this is the first report of an SLE and KS association. The exact relationship between the two conditions in our patient is difficult to determine with certainty, as a number of clinical features, including positive antiphospholipid antibodies, persistent hypogammaglobulinemia and the episode of convulsions may occur in both conditions, suggesting potential overlap of KS and SLE. The combination of a high susceptibility towards infections and an autoimmune disorder present a great challenge when trying to achieve the optimum therapy which will enable the patient to stay on the thin line of remission. This case report emphasizes the value of WES as a powerful tool for the diagnosis of rare disorders and/or unusual disease presentations of possible genetic cause.

Novel and rare functional genomic variants in multiple autoimmune syndrome and Sjögren's syndrome.

BACKGROUND: Multiple autoimmune syndrome (MAS), an extreme phenotype of autoimmune disorders, is a very well suited trait to tackle genomic variants of these conditions. Whole exome sequencing (WES) is a widely used strategy for detection of protein coding and splicing variants associated with inherited diseases. METHODS: The DNA of eight patients affected by MAS [all of whom presenting with Sjögren's syndrome (SS)], four patients affected by SS alone and 38 unaffected individuals, were subject to WES. Filters to identify novel and rare functional (pathogenic-deleterious) homozygous and/or compound heterozygous variants in these patients and controls were applied. Bioinformatics tools such as the Human gene connectome as well as pathway and network analysis were applied to test overrepresentation of genes harbouring these variants in critical pathways and networks involved in autoimmunity. RESULTS: Eleven novel and rare functional variants were identified in cases but not in controls, harboured in: MACF1, KIAA0754, DUSP12, ICA1, CELA1, LRP1/STAT6, GRIN3B, ANKLE1, TMEM161A, and FKRP. These were subsequently subject to network analysis and their functional relatedness to genes already associated with autoimmunity was evaluated. Notably, the LRP1/STAT6 novel mutation was homozygous in one MAS affected patient and heterozygous in another. LRP1/STAT6 disclosed the strongest plausibility for autoimmunity. LRP1/STAT6 are involved in extracellular and intracellular anti-inflammatory pathways that play key roles in maintaining the homeostasis of the immune system. Further; networks, pathways, and interaction analyses showed that LRP1 is functionally related to the HLA-B and IL10 genes and it has a substantial impact within immunological pathways and/or reaction to bacterial and other foreign proteins (phagocytosis, regulation of phospholipase A2 activity, negative regulation of apoptosis and response to lipopolysaccharides). Further, ICA1 and STAT6 were also closely related to AIRE and IRF5, two very well known autoimmunity genes. CONCLUSIONS: Novel and rare exonic mutations that may account for autoimmunity were identified. Among those, the LRP1/STAT6 novel mutation has the strongest case for being categorised as potentially causative of MAS given the presence of intriguing patterns of functional interaction with other major genes shaping autoimmunity.

Candidate gene discovery in autoimmunity by using extreme phenotypes, next generation sequencing and whole exome capture.

Whole exome sequencing (WES) is a widely used strategy for detection of protein coding and splicing variants associated with inherited diseases. Many studies have shown that the strategy has been broad and proficient due to its ability in detecting a high proportion of disease causing variants, using only a small portion of the genome. In this review we outline the main steps involved in WES, the comprehensive analysis of the massive data obtained including the genomic capture, amplification, sequencing, alignment, curating, filtering and genetic analysis to determine the presence of candidate variants with potential pathogenic/functional effect. Further, we propose that the multiple autoimmune syndrome, an extreme phenotype of autoimmune disorders, is a very well suited trait to tackle genomic variants of major effect underpinning the lost of self-tolerance.

Single nucleotide variants (SNVs) define senescence-accelerated SAMP8 mice, a model of a geriatric condition.

One of the major challenges in neurodegenerative research is modeling systemic aging. Here, senescence-accelerated mice such as the multigenic SAMP8 (senescence accelerated prone 8) mice are useful as they are characterized by an early manifestation of senescence that includes a shortened lifespan and impaired brain and immune functions. While SAMP8 mice are widely used tools to address aging and neurodegenerative conditions such as Alzheimer's disease (AD), the underlying gene mutations are not known. To make the SAMP8 strain a more versatile and useful research tool, we performed exome sequencing, using SAMR1 (senescence accelerated mouse resistant 1) mice as controls. We identified 51 SNVs (single nucleotide variants) that discriminate SAMP8 from SAMR1 mice. Using the prediction tool Polyphen2, we were able to subdivide the SNVs into four categories: splice variants, probably damaging, possibly damaging, and benign. Of these genes, a significant fraction is predicted to be expressed in the brain. Our data present these genes for a more detailed analysis in aging and neurodegeneration studies. They underscore the usefulness of SAMP8 mice as an animal model to study fundamental mechanisms of both aging and the pathogenesis of AD.

Accurate and reliable high-throughput detection of copy number variation in the human genome.

This study describes a new tool for accurate and reliable high-throughput detection of copy number variation in the human genome. We have constructed a large-insert clone DNA microarray covering the entire human genome in tiling path resolution that we have used to identify copy number variation in human populations. Crucial to this study has been the development of a robust array platform and analytic process for the automated identification of copy number variants (CNVs). The array consists of 26,574 clones covering 93.7% of euchromatic regions. Clones were selected primarily from the published "Golden Path," and mapping was confirmed by fingerprinting and BAC-end sequencing. Array performance was extensively tested by a series of validation assays. These included determining the hybridization characteristics of each individual clone on the array by chromosome-specific add-in experiments. Estimation of data reproducibility and false-positive/negative rates was carried out using self-self hybridizations, replicate experiments, and independent validations of CNVs. Based on these studies, we developed a variance-based automatic copy number detection analysis process (CNVfinder) and have demonstrated its robustness by comparison with the SW-ARRAY method.