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Introduction Hereditary heart diseases are most often characterized by autosomal dominant inheritance and delayed cardiac expression. Predictive genetic testing (PGT) is offered to asymptomatic relatives to allow targeted medical care with early therapeutics in order to reduce the risk of complications. Purpose The aim of this study was to evaluate the psychological and socio-professional impact of predictive genetic testing in hereditary heart diseases through a prospective and retrospective study. Methods & results This multicentric French study involved 20 expert centers in hereditary heart diseases. We included 517 adult relatives (42.3 ± 16.7 years, 60.6% females) who performed PGT (prospective study: n = 264, retrospective study: n = 253). The opinion and experience were collected via auto-questionnaires, at various moments in the prospective study, with different items and validated scales (STAI and IES). In the prospective study, family history was characterized by cardiomyopathy (88.4%) and channelopathies (11.6%). The main motivations for performing the test were: “to remove doubt” (65.3%), “for children” (64.0%), “to benefit from medical supervision” (34.9%). A mutation was present in 39.4% of relatives. No regret was expressed after testing (only 2.3% regrets). The result did not lead to a socio-professional change or family relationship change in 60.7%. Among those who had a change, it was perceived as unfavorable for only 3%. The level of anxiety (STAI) increases before the test result and decreased to return to baseline. Subjects with depression history were more likely to develop anxiety at long-term after multivariate analyses (P = 0.004). Conclusions Our results show that contrary to a widespread opinion, the medical benefit was not the main motivation for predictive genetic testing. In most cases, no or marginal adverse psychological and socio-professional impact of genetic testing was observed when performed by a team expert in predictive testing.

Background Mitral valve prolapse (MVP) is a frequent and heterogeneous valve desease. To date, mutations of only DCSH1 and FLNA have been identified in non-syndromic MVP but account for a small subset of cases. Purpose Our study aims to identify new genetic variants in non syndromic MVP. Methods We performed whole-exome sequencing in a family including a one year-old female patient with a severe mitral regurgitation due to a complex MVP and her unaffected parents. Results We identified a missense mutation in a gene known to be involved in cardiomyopathies but not in MVP. No mutation was found in DCSH1 and FLNA. The unaffected mother carried the same mutation as the index case. Functional studies on a mouse model showed that this gene is expressed in cells contributing to the mitral subvalvular apparatus development. Among thirteen patients with cardiomyopathy associated with mutation of the same gene, four had concomitant MVP. Conclusion Our study identified a candidate gene for MVP potentially associated with cardiomyopathy.

Background The etiological spectrum of hypertrophic cardiomypathies (HCM) is wide and some rare causes are largely underdiagnosed. Purpose Our aim is to assess the impact of the next generation sequencing (NGS) for the diagnosis of two rare genetic diseases: Fabry disease and hereditary transthyretin amyloidosis (GLA & TTR genes) in a population with HCM. Method We analysed 300 independent patients with HCM through a next generation sequencing (NGS) strategy using a panel of 107 genes involved in hereditary cardiomyopathies. The sequencing was performed by liquid-based capture of targeted areas (Nimblegen®) using HiSeq2500 device (Illumina®). The data were specifically reanalysed for this study, adjusting rules for pathogenicity interpretation based on ACMG guidelines and considering some high variant frequencies in these two genes. Results We studied 300 patients, 217 males & 83 females, mean age of 46 years. The NGS resulted in the identification of 266 variants (all classes included) in the 2 genes of interest (GLA: 189 variants, TTR: 77 variants). Further analysis led us to identify 4 causal mutations (pathogenic or probably pathogenic): 3 in GLA (p.Arg118Cys, p.Val269Ala, p.Ala143Thr) and one in TTR (p.Val142Ile). Fabry disease or amyloidosis were not diagnosed before NGS analysis. In the cohort, the prevalence was 1.3% for Fabry disease and 0.3% for ATTR. Conclusion NGS using a large panel is able to identify rare causes of HCM which were not previously suspected. The observed prevalences are comparable to those reported in the literature for the Fabry disease but are lower than those reported for the ATTR which could be due to the relatively young age of the patients in our analysed cohort. Our results support a systematic NGS screening with a large panel including GLA and TTR genes in patients referred for HCM. This screening is especially important as patients carrying Fabry or ATTR diseases may benefit from new specific therapies.

Background Hypertrophic cardiomyopathy (HCM) is a frequent hereditary cardiac disease and a major cause of sudden cardiac death (SCD). Although very useful, ESC risk score's predictive value has been interrogated since it was retrospective and did not include MRI parameters and new echocardiographic markers. Purpose To assess the additional value of new echocardiographic and MRI parameters in predicting SCD and outcome in patients with HCM. Methods Between 2007 and 2017, 307 patients with HCM were prospectively included and followed for 1.63 years. In addition to conventional prognostic factors, all patients underwent cardiac MRI evaluation of late gadolinium enhancement (LGE), and echocardiographic measurements of LV and LA volumes and strains, including left atrial peak longitudinal strain (PALS) and left atrial peak contraction strain (PACS). Primary end-point was SCD or appropriate defibrillator therapy. Secondary end-point was a composite end-point including death, hospitalization for heart failure, new-onset of atrial fibrillation, need for septal ablation, myomectomy, or heart transplantation. Results Among the 307 patients, 6 patients (2%) died and the secondary end-point occurred in 65 (21%). Factors associated with SCD by univariate analysis were low LVEF [HR 0.91 (0.93–0.99)] impaired PALS [HR 0.86 (0.72–0.97)], and moderate mitral regurgitation (MR). Factors associated with the secondary end-point were impaired LV GLS [HR 1.23 (1.13; 1.35)], impaired LA 4-chamber PALS [HR 0.94 (0.91; 0.97)] and PACS [HR 0.91 (0.86; 95)], LA 2 chamber PALS [HR 0.93 (0.89; 0.96)] and PACS [HR 0.86 (0.83;0. 94)], as well as TTE and MRI MR, and presence of MRI LGE. Impaired LA 4-chamber PALS remained as an independent predictor for the composite end-point [HR 0.92 (0.87; 0.97)] after adjustment. Conclusion This study suggests an additive prognostic value of an impaired LV and LA TTE strain, the presence of MR, and MRI LGE, to the classical ESC 7 recommended risk factors.

Background and objective Hypertrophic cardiomyopathy (HCM) is one of the leading causes of sudden cardiac death in young adults, with a prevalence of 1/500 in the general population. HCM is a genetic disease usually related to a sarcomeric gene mutation. Despite advances in knowledge, elucidation of the genetic cause is reached in only 30–60% of cases with conventional Sanger sequencing and analysis of a limited number of genes (usually the five major sarcomeric genes). We hypothesized that high-throughput sequencing of a large panel of genes will allow a more comprehensive evaluation of the etiologic spectrum of HCM. Methods and results We used high-throughput sequencing technology, with a panel of 107 genes (all the various cardiomyopathies and arrhythmia genes) that we recently developed (Nimblegen capture then Illumina MiSeq sequencing), in a cohort of 97 unrelated patients with HCM. We detected 2740 variants including 99 variants that we classified as pathogenic using restrictive criteria. A pathogenic mutation was identified (i) in 31 patients (32% of cohort of patients) in the group of 5 conventional sarcomeric genes (MYBPC3, MYH7, TNNT2, MYL2, TNNI3) including patients with multiple mutations, (ii) in 8 patients (8%) with a mutation in the group of additional sarcomeric genes (such as MYH6), (iii) in 4 patients (4%) with a mutation in the group of non-sarcomeric genes previously associated to HCM (such as GLA responsible for Fabry disease) and (iv) in additional patients with a mutation in new genes not yet reported in HCM (such as AKAP9). Conclusion High-throughput sequencing of a large panel of genes associated with hereditary heart diseases allowed us to determine the large genetic spectrum of HCM. We confirmed the prominent role of sarcomeric genes, highlighted the role of non-sarcomeric causes (some with specific therapeutics) and identified mutations in potential new genes responsible for the disease.

Introduction Left ventricular non-compaction (LVNC) is a rare cardiomyopathy that may be of genetic origin, however few data are available about the global yield of mutation screening, the spectrum of genes and allelic variations. Purpose The aim of this prospective study was to better characterize the allelic and genetic spectrum of isolated LVNC in a cohort of 95 unrelated adult patients through the molecular investigation of a custom panel of 107 genes involved in various cardiomyopathies and cardiac arrhythmias. Results Sixty pathogenic or probably pathogenic variants, including 47 novel ones, were identified in 44 patients (46.3%) including 31 patients (32.6%) with single variant and 13 patients with complex genotypes (13.6%). The most prevalent genes were TTN, then HCN4, MYH7, RYR2, MYH6, and MYBPC3. The genotype-phenotype correlation and the major clinical outcome enhanced the fact that mutated patients tended to have younger age of diagnosis. Interestingly the mutation yield was significantly higher in youngest patients 65 years (2/11, 18,2%, P = 0.02). The LV mean ejection fraction in patient with a mutation in sarcomeric genes was lower than in patients mutated in non-sarcomeric genes (41.7% vs. 52.7%, P = 0.05). The distribution includes 14 genes previously reported in LVNC and 13 additional candidate genes. Discussion Our results showed that LVNC is basically a genetic disease and support genetic counselling and cardiac screening in relatives. There is a large genetic heterogeneity, with predominant TTN mutations and a distribution close to the one observed in dilated cardiomyopathy but with specific genes such as HCN4. The prevalence of complex genotypes in these patients is important to notice in the context of genetic counselling. We also identified 13 potential new genes associated with LVNC.

Background and objectives: Hypertrophic cardiomyopathy (HCM) is expected to be caused by a heterozygous mutation in one of the 5 main sarcomere genes (MYBPC3, MYH7, TNNT2, MYL2, TNNI3). However, the routine diagnostic strategy consisting of the sequencing of these 5 genes allows identification of a mutation in only 50% of familial or sporadic cases, limiting accurate genetic counseling in families and predictive diagnosis in at-risk subjects. Purpose: We aimed at evaluating the value of Whole Exome Sequencing (WES), comparing its diagnostic yield with the routine diagnostic strategy, and clarifying the genetic spectrum of HCM. Methods: We performed WES in a large series of 200 new unrelated patients with primary HCM using the Agilent SureSelect V6 technology on Illumina Hiseq 2500. Patients were recruited between June 2015 and October 2016 in 5 French centers. In a first step of analysis, a panel of 145 genes involved in various hereditary cardiac diseases was searched for mutations. Bioinformatics analyses were performed in our lab. Only "certainly" (class 5) or "probably" pathogenic (class 4) mutations were considered, according to current guidelines Results: A total of 565 filtered variants predicted as pathogenic in 111 genes were retained after bioinformatics analysis, literature and databases review. The main results are the following:-A mutation in 1 of the 5 main sarcomere genes was observed in only 72 (36%) patients, with no mutation on the TNNI3 gene.-Conversely, 495 other pathogenic mutations were identified in 185 patients, giving a total 92.5% detection rate of at least one pathogenic gene mutation. Among them, the most prevalent mutated genes were FLNC, LDB3, MYPN, ANK2, RYR2 and NEBL. In addition, unexpected diagnosis of treatable affections such as Fabry disease (n=1) and TTR amyloidosis (n=1) were identified by WES analysis-A single mutation was identified in only 27 patients (13.5% of cases). In 158 patients (79%), multiple variants were identified with 2 to 8 mutations per patient.-Finally, in only 15 patients (7.5%), no mutation was identified in this panel of 145 genes. Conclusions: 1. Exome sequencing improves the diagnostic output in HCM with 92.5% of patients carrying at least one pathogenic mutation in a panel of 145 genes involved in various hereditary cardiac diseases 2. Genetic heterogeneity is much larger than expected with multiple variants in sarcomere genes, but also non-sarcomere, and ion channel genes unexpected in HCM. 3. Early unexpected diagnosis of Fabry disease or TTR amyloidosis can be obtained by our strategy of one-step large genetic analysis. 4. Our results suggest that the commonly accepted monogenic model of HCM involving one mutation in one gene is not the major mechanism in HCM. Rather, oligogenism with 1 major and several minor variants is our proposed new pathogenic mechanism in HCM.

Resume Introduction Le diagnostic de myopathie facioscapulo-humerale de type 1 (FSHD1) repose sur un examen clinique evocateur et la presence d’une contraction pathogene des unites repetees (UR) dans la portion sub-telomerique du chromosome 4 (4q35). Etat des connaissances Trois grandes formes peuvent etre distinguees : la forme classique associee a des deletions de quatre a sept UR de severite variable, la forme severe infantile debutant avant dix ans associee a des deletions d’une a trois UR et la forme dite benigne, associee a des deletions de huit a dix UR. La presence d’une atteinte selective asymetrique des muscles faciaux et scapulaires fait fortement evoquer le diagnostic de FSHD1. Lorsque ce diagnostic est suspecte, la biologie moleculaire doit etre realisee en premiere intention. En l’absence de confirmation genetique, des examens complementaires tels que l’ENMG et la biopsie musculaire doivent etre realises a la recherche d’une autre etiologie. Si aucune autre etiologie n’est retenue, le diagnostic de FSHD2 doit etre envisage. Perspectives et conclusion Le Southern Blot classiquement utilise pour le diagnostic moleculaire peut etre d’interpretation delicate. La technique de peignage moleculaire permet une visualisation directe et complete de la region D4Z4 et ameliore la rentabilite du diagnostic moleculaire de la FSHD1.

Introduction La maladie de Parkinson (MP), sous-tendue par des facteurs environnementaux et genetiques, connait plusieurs genes deja identifies. La microdeletion 22q11.2 a ete recemment rapportee comme nouvelle cause genetique potentielle. Objectifs Decrire les caracteristiques du syndrome parkinsonien associe a la microdeletion 22q11 dont l’expression phenotypique classique est le syndrome de DiGeorge (DGS). Methodes Nous avons recense les cas francais de DGS parmi les malades parkinsoniens (DGS-MP), en sollicitant les centres du reseau Parkinson national. Le questionnaire colligeait les donnees administratives et socio-educatives, phenotypiques et genetiques ainsi que les caracteristiques cliniques du syndrome parkinsonien (aspects moteurs et non moteurs, complications) et ses explorations complementaires. Les resultats ont ete resumes par leurs statistiques descriptives (effectif, mediane [interquartile], moyenne [ecart-type]). Resultats Sept centres avaient au moins un patient concerne, soient 10 patients (8 hommes, 2 femmes). L’âge median etait 38,5 ans au diagnostic de MP [EIQ : 7,8 ans], versus 42 ans pour celui de DGS [EIQ : 8,8 ans]. Neuf sur dix avaient une dysmorphie typique. Sept sur huit avaient une DOPA-sensibilite depassant 50 % et 3/8 depassant 70 %. Trois patients avaient une stimulation cerebrale profonde. Le score moyen de la Mattis-DRS etait 130/144 [ET : 3,9]. Discussion Cette cohorte de patients DGS-MP est, a notre connaissance, de loin la plus grande etudiee. Les patients DGS-MP francais ont un phenotype parkinsonien tres pur (grande DOPA-sensibilite, absence de drapeaux rouges) ; 3 d’entre eux etaient stimules. L’origine potentielle (DGS) a logiquement ete globalement suspectee apres le diagnostic de MP. L’evolution etait ensuite tres severe chez certains. Conclusion Le syndrome de DiGeorge pourrait constituer une nouvelle forme de MP, dont le phenotype apparait tres pur. Ainsi devant une MP du sujet jeune, une recherche de DGS parait souhaitable. Informations complementaires Nous remercions tous les centres du reseau Parkinson pour leur aide precieuse.

Facio-Scapulo-Humeral Dystrophy (FSHD) is an enigmatic pathology. This autosomal dominant disorder is linked to deletion within a D4Z4 macrosatellite in the subtelomeric 4q35 region. The gene product leading to the disease has not been clearly identified and epigenetic changes are likely key players in the disease since beside reduction in the number of repeats, D4Z4 is hypomethylated in FSHD. Within D4Z4, DUX4 has been found upregulated in patients. Different DUX4 transcripts have been described Production of a long transcript encompassing the DUX4 sequence and a region distal to D4Z4 encoding a toxic protein has been proposed as the cause of disease. A causal link between DUX4 expression and D4Z4 hypomethylation subsequent to array shortening has been proposed but never firmly established. We analyzed DUX4 expression as well as the expression of 4q35 genes and muscular markers in FSHD and non-FSHD biopsies during fetal development and in adults in a large cohort of samples. We highlight several genes whose expression differs between control and FSHD samples. Furthermore, we detected DUX4 transcripts in both groups, in muscle but also in other tissues indicating that expression of the long transcript is not restricted to FSHD muscles. Using FSHD and control myoblasts, we showed that DUX4 expression is induced by hypomethylation after knock-down of DNA methyltransferases, independently of D4Z4 array shortening. Our result tends toward a stochastic activation DUX4 transcription rather than a muscle-specific expression pattern in FSHD patients. The mechanism precluding onset and progression of FSHD remains highly controversial and still debated. Our work is the first to uncover changes in gene expression in fetuses carrying a D4Z4-linked 4q35 defect. These results are important for understanding FSHD but also in general, to understand how epigenetic mechanism modulate the transcription of repetitive DNA sequences in the human genome especially in the human diseases.

‘‘calpainopathy”) is caused by defects in p94/calpain 3, which is the skeletal muscle-specific member of Ca-dependent cysteine protease ‘‘calpain”. Mammals have 15 genes for calpains (CAPN1 CAPN3, CAPN5 CAPN16), which are involved in a variety of cellular functions, and p94 is encoded by CAPN3. Particularly, mouse gene knock-out of Capn2, which encodes catalytic subunit of ubiquitous m-calpain, causes embryonic lethality, and that ofCapn3 results in calpainopathy inmice, indicating an essential role of calpain inmammalian life and health. However, the mechanism of p94’s function in the pathogenesis of calpainopathy remains unclear. Here, we demonstrate that the stretch-dependent p94 distribution plays a crucial role in the pathogenesis of calpainopathy, using p94:C129S ‘‘knock-in” (p94CS-KI) mice, in which the endogenous p94 was replaced with a proteolytically inactive but structurally intact p94:C129Smutant protein. The p94CS-KImice developed a progressivemuscular dystrophy, which was exacerbated by ageing or exercise, although their phenotype (myofibril integrity, serum CK levels, etc.) is less severe than that of p94 knock-out (p94KO) mice. The exercise-induced muscle degeneration in p94CS-KI mice was associated with an inefficient redistribution of p94:C129S in stretched sarcomeres. Furthermore, the p94CS-KI mice showed impaired adaptation to physical stress, accompaniedbyanexercise-dependent alteration in themuscle ankyrin-repeat protein-2 (MARP2) level. These findings indicate that the stretch-induced dynamic redistribution of p94 is affected by its protease activity and is essential to protect skeletal muscle cells from degeneration, particularly under physical stress.