Project description:Histologic diagnosis of sellar masses can be challenging, particularly in rare neoplasms and tumors without definitive biomarkers. DNA methylation has recently emerged as a useful diagnostic tool. To illustrate the clinical utility of machine-learning-based DNA methylation classifiers, we report a rare case of primary sellar esthesioneuroblastoma diagnosed by DNA methylation classificiation but histologically mimicking a nonfunctioning pituitary adenoma.
Project description:The Australian Acute Care Genomics program provides ultra-rapid diagnostic testing to critically ill infants and children with suspected genetic conditions. Over two years, we performed whole genome sequencing (WGS) in 290 families, with average time to result of 2.9 days, and diagnostic yield of 47%. We performed additional bioinformatic analyses and transcriptome sequencing in all patients who remained undiagnosed. Long-read sequencing and functional assays, ranging from clinically accredited enzyme analysis to bespoke quantitative proteomics, were deployed in selected cases. This resulted in an additional 19 diagnoses, and an overall diagnostic yield of 54%. Diagnostic variants ranged from structural chromosomal abnormalities through to an intronic retrotransposon, disrupting splicing. Critical care management changed in 120 diagnosed patients (77%). Results informed precision treatments; surgical and transplant decisions; and palliation in 94 (60%). We propose that integration of multi-omic approaches into mainstream diagnostic practice is necessary to realise the full potential of genomic testing.
Project description:Lysosomal storage diseases (LSDs) are a heterogeneous group of genetic disorders with variable degrees of severity and a broad phenotypic spectrum, which may overlap with a number of other conditions. While individually rare, as a group LSDs affect a significant number of patients, placing an important burden on affected individuals and their families but also on national health care systems worldwide. Here, we present our results on the use of an in-house customized next-generation sequencing (NGS) panel of genes related to lysosome function as a first-line molecular test for the diagnosis of LSDs. Ultimately, our goal is to provide a fast and effective tool to screen for virtually all LSDs in a single run, thus contributing to decrease the diagnostic odyssey, accelerating the time to diagnosis. Our study enrolled a group of 23 patients with variable degrees of clinical and/or biochemical suspicion of LSD. Briefly, NGS analysis data workflow, followed by segregation analysis allowed the characterization of approximately 41% of the analyzed patients and the identification of 10 different pathogenic variants, underlying nine LSDs. Importantly, four of those variants were novel, and, when applicable, their effect over protein structure was evaluated through in silico analysis. One of the novel pathogenic variants was identified in the GM2A gene, which is associated with an ultra-rare (or misdiagnosed) LSD, the AB variant of GM2 Gangliosidosis. Overall, this case series highlights not only the major advantages of NGS-based diagnostic approaches but also, to some extent, its limitations ultimately promoting a reflection on the role of targeted panels as a primary tool for the prompt characterization of LSD patients.
Project description:Congenital diarrheal disorders (CDDs) are early-onset enteropathies generally inherited as autosomal recessive traits. Most patients with CDDs require rapid diagnosis as they need immediate and specific therapy to avoid a poor prognosis, but their clinical picture is often overlapping with a myriad of nongenetic diarrheal diseases. We developed a next-generation sequencing (NGS) panel for the analysis of 92 CDD-related genes, by which we analyzed patients suspect for CDD, among which were (i) three patients with sucrose-isomaltase deficiency; (ii) four patients with microvillous inclusion disease; (iii) five patients with congenital tufting enteropathy; (iv) eight patients with glucose-galactose malabsorption; (v) five patients with congenital chloride diarrhea. In all cases, we identified the mutations in the disease-gene, among which were several novel mutations for which we defined pathogenicity using a combination of bioinformatic tools. Although CDDs are rare, all together, they have an incidence of about 1%. Considering that the clinical picture of these disorders is often confusing, a CDD-related multigene NGS panel contributes to unequivocal and rapid diagnosis, which also reduces the need for invasive procedures.
Project description:The demo datasets available for MSCohort analysis. You can download to inspect their formats and practice using the software tool. This dataset contains raw files of 7 urine QC samples, spectronaut analysis results and MSCohort report results
Project description:The term hereditary ataxia (HA) refers to a heterogeneous group of neurological disorders with multiple genetic etiologies and a wide spectrum of ataxia-dominated phenotypes. Massive gene analysis in next-generation sequencing has entered the HA scenario, broadening our genetic and clinical knowledge of these conditions. In this study, we employed a targeted resequencing panel (TRP) in a large and highly heterogeneous cohort of 377 patients with a clinical diagnosis of HA, but no molecular diagnosis on routine genetic tests. We obtained a positive result (genetic diagnosis) in 33.2% of the patients, a rate significantly higher than those reported in similar studies employing TRP (average 19.4%), and in line with those performed using exome sequencing (ES, average 34.6%). Moreover, 15.6% of the patients had an uncertain molecular diagnosis. STUB1, PRKCG, and SPG7 were the most common causative genes. A comparison with published literature data showed that our panel would have identified 97% of the positive cases reported in previous TRP-based studies and 92% of those diagnosed by ES. Proper use of multigene panels, when combined with detailed phenotypic data, seems to be even more efficient than ES in clinical practice.
Project description:Only half of individuals with suspected rare diseases receive a definitive genetic diagnosis following genomic testing. A genetic diagnosis allows access to appropriate patient care and reduces the number of potentially unnecessary interventions and related healthcare costs. Here, we demonstrate that an untargeted quantitative mass-spectrometry approach quantifying >6,000 proteins in primary fibroblasts representing >80% of known mitochondrial disease genes can provide functional evidence for 88% of individuals in a cohort of known primary mitochondrial diseases. We profiled >90 individuals, including 28 with confirmed disease and diagnosed 6 individuals with variants in both nuclear and mitochondrial genes. Lastly, we developed an ultra-rapid proteomics pipeline using minimally invasive peripheral blood mononuclear cells to support upgrade of variant pathogenicity in as little as 54 hours in critically ill infants with suspected mitochondrial disorders. This study supports the integration of a single untargeted proteomics test into routine diagnostic practice for the diagnosis of rare genetic disorders in clinically actionable timelines, offering a paradigm shift for the functional validation of genetic variants.
Project description:Isobaric labeling is a powerful strategy for quantitative mass spectrometry-based proteomic investigations. A complication of such analyses has been the co-isolation of multiple analytes of similar mass-to-charge resulting in the distortion of relative protein abundance measurements across samples. When properly implemented, triple-stage mass spectrometry and synchronous precursor selection (SPS-MS3) can reduce the occurrence of this phenomena, referred to as ion interference. However, no diagnostic tool is available currently to rapidly and accurately assess ion interference. To address this need, we developed a multiplexed TMT-based standard, termed the triple knockout (TKO). This standard is comprised of three yeast proteomes in triplicate, each from a strain deficient in a highly abundant protein (Met6, Pfk2, or Ura2). The relative abundance patterns of these proteins, which can be inferred from dozens of peptide measurements, are representative of ion interference in peptide quantification. We expect no signal in channels where the protein is knocked out, permitting maximum sensitivity for measurements of ion interference against a null background. Here, we emphasize the need to investigate further ion interference-generated ratio distortion and promote the TKO standard as a tool to investigate such issues.