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Aims The purpose of this study was to assess the value of genetic testing in addition to a comprehensive clinical evaluation, as part of the diagnostic work-up of elite and/or amateur Italian athletes referred for suspicion of inherited cardiac disease, following a pre-participation screening programme.Methods Between January 2009–December 2018, of 5892 consecutive participants, 61 athletes were investigated: 30 elite and 31 amateur athletes. Elite and amateur athletes were selected, on the basis of clinical suspicion for inherited cardiac disease, from two experienced centres for a comprehensive cardiovascular evaluation. Furthermore, the elite and amateur athletes were investigated for variants at DNA level up to 138 genes suspected to bear predisposition for possible cardiac arrest or even sudden cardiac death.Results Of these 61 selected subjects, six (10%) had diagnosis made possible by a deeper clinical evaluation, while genetic testing allowed a definite diagnosis in eight (13%). The presence of >3 clinical markers (i.e. family history, electrocardiogram and/or echocardiographic abnormalities, exercise-induced ventricular arrhythmias) was associated with a higher probability of positive genetic diagnosis (75%), compared with the presence of two or one clinical markers (14.2%, 8.1%, respectively, p-value = 0.004).Conclusion A combined clinical and genetic evaluation, based on the subtle evidence of clinical markers for inherited disease, was able to identify an inherited cardiac disease in about one-quarter of the examined athletes.

OBJECTIVES:Celiac disease (CD)-associated duodenal dysbiosis has not yet been clearly defined, and the mechanisms by which CD-associated dysbiosis could concur to CD development or exacerbation are unknown. In this study, we analyzed the duodenal microbiome of CD patients.METHODS:The microbiome was evaluated in duodenal biopsy samples of 20 adult patients with active CD, 6 CD patients on a gluten-free diet, and 15 controls by DNA sequencing of 16S ribosomal RNA libraries. Bacterial species were cultured, isolated and identified by mass spectrometry. Isolated bacterial species were used to infect CaCo-2 cells, and to stimulate normal duodenal explants and cultured human and murine dendritic cells (DCs). Inflammatory markers and cytokines were evaluated by immunofluorescence and ELISA, respectively.RESULTS:Proteobacteria was the most abundant and Firmicutes and Actinobacteria the least abundant phyla in the microbiome profiles of active CD patients. Members of the Neisseria genus (Betaproteobacteria class) were significantly more abundant in active CD patients than in the other two groups (P=0.03). Neisseria flavescens (CD-Nf) was the most abundant Neisseria species in active CD duodenum. Whole-genome sequencing of CD-Nf and control-Nf showed genetic diversity of the iron acquisition systems and of some hemoglobin-related genes. CD-Nf was able to escape the lysosomal compartment in CaCo-2 cells and to induce an inflammatory response in DCs and in ex-vivo mucosal explants.CONCLUSIONS:Marked dysbiosis and an abundance of a peculiar CD-Nf strain characterize the duodenal microbiome in active CD patients thus suggesting that the CD-associated microbiota could contribute to the many inflammatory signals in this disorder.

The diffusion of Next Generation Sequencing (NGS)-based approaches has allowed the identification of cardiomyopathies and channelopathies pathogenic mutations in more than 200 different genes. Since also genes considered uncommon for a clinical phenotype are now included in molecular testing, the detection rate of disease-causing variants is increased. Here, we report the prevalence of genetic variants detected in a cohort of 133 patients, among which 73 showed complex or borderline phenotypes or a positive family history for SCD. The analysis was conducted by analyzing an enlarged panel of 129 genes, including 60 main genes associated to the different genetic cardiomyopathies (HCM, DCM, ACM, LQTS, BrS) and 69 genes without a strong or definitive evidence of disease association according to the NIH-funded Clinical Genome Resource (ClinGen), here named “uncommon genes”.We identified 82 variants, of which 50 (61%) were identified in uncommon genes. Among these, thirty-five (70%) were reported as variants of unknown significance (VUSs), thirteen (26%) as pathogenic (P) or likely pathogenic (LP) mutations and 2 (4%) as novel (likely) benign (B/LB) variants, according to the American College of Medical Genetics (ACMG) classification. Interestingly, about 85% of P/LP variants identified in uncommon genes were in patients showing complex/unclear/borderline phenotypes or a positive family history for SCD.These data support the need for an extended genetic testing, including genes that are not usually explored due to a currently poor association with the clinical phenotype, particularly when phenotype is borderline, in order to increase the diagnostic sensitivity of inherited cardiomyopathies and channelopathies genetic testing.

Introduction:Anderson-Fabry disease (AFD) is a systemic disorder caused by impaired alpha-galactosidase (GLA) activity, leading to a progressive cardiomyopathy, with hypertrophy and diastolic dysfunction. However, the molecular mechanisms underlying these features are unknown.Aim:To explore the role of mitochondria as a pathogenic mechanism of cardiac dysfunction in AFD.Methods:We tested a transgenic mouse that lacks endogenous GLA and expresses human R301Q-GLA [Tg/GLA knockout]. We performed serial ecochardiographic, histological, and biochemical analyses on cardiac tissue and single cell contractility on isolated adult cardiomyocytes (CM). Moreover, we assessed mitochondrial morphology/function in mouse embryonic fibroblasts (MEFs).Results:AFD-MEFs display an impaired mitochondrial respiration and reduced ATP synthesis. Increased mitochondrial levels of DRP1, LC3II, and MFN-ubiquitination along with accumulation of fragmented mitochondria and autophagosomes indicate the presence of mitophagy-targeted mitochondria that were not removed. Reduced PGC-1a and mitochondrial-DNA synthesis in AFD-MEFs indicate impaired mitochondrial biogenesis as well. Altogether, our data indicate impaired mitophagy and quality control of AFD-mitochondria. At echocardiography, AFD mice showed diastolic dysfunction and hypertrophy starting from 9 months. Isolated AFD-CMs exhibit reduced inotropic response to isoproterenol. Remarkably, alterations of cardiac mitochondrial function were observed starting from 3 months, including increased levels of MFN2-ubiquitination, DRP1 and LC3II, decreased levels of PGC-1a along with accumulation of disarranged mitochondria and autophagosomes. Frank impairment of mitochondrial respiration in AFD-CMs and reduced myocardial ATP-content was detected from 6 months, together with increased release of Cytochrome-C in the cytosol. Strikingly, mitochondrial dysfunction was also detected in fibroblasts isolated from AFD patients, which have a significantly reduced electron transport chain activity.Conclusions:In AFD, energetic alterations associated with impaired autophagy/mitophagy, are evident at 3 months and progressively lead to cardiac hypertrophy and dysfunction.

Hypertrophic cardiomyopathy is a relatively frequent disease with a prevalence of 0.2% worldwide and a remarkable genetic heterogeneity, with more than 30 causative genes reported to date. Current PCR-based strategies are inadequate for genomic investigations involving many candidate genes. Here, we report a next-generation sequencing procedure associated with DNA sequence capture that is able to sequence 202 cardiomyopathy-related genes simultaneously. We developed a complementary data analysis pipeline to select and prioritize genetic variants. The overall procedure can screen a large number of target genes simultaneously, thereby potentially revealing new disease-causing and modifier genes. By using this procedure, we analyzed hypertrophic cardiomyopathy patients in a shorter time and at a lower cost than with current procedures. The specificity of the next-generation sequencing–based procedure is at least as good as other techniques routinely used for mutation searching, and the sensitivity is much better. Analysis of the results showed some novel variants potentially involved in the pathogenesis of hypertrophic cardiomyopathy: a missense mutation in MYH7and a nonsense variant in INS-IGF2(patient 1), a splicing variant in MYBPC3and an indel/frameshift variant in KCNQ1(patient 2), and two concomitant variations in CACNA1C(patient 3). Sequencing of DNA from the three patients within a pool allowed detection of most variants identified in each individual patient, indicating that this approach is a feasible and cost-effective procedure.