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Next-generation sequencing techniques enable unsolicited findings to be detected. This discovery raises ethical questions concerning the return of these findings. Our study aimed to highlight the views of the general public, patients under supervision and health professionals concerning the acceptability of disclosing unsolicited results to patients. In total, 449 participants assessed scenarios, consisted of all combinations of three factors (patient's information and consent, prevention and treatment of the unsolicited disease and doctor's decision). The response profiles were grouped into six clusters. The participants took ethical aspects into account, but health professionals also considered the medical aspects to a greater extent. [ABSTRACT FROM AUTHOR]

Background: Segmental progeroid syndromes are a heterogeneous group of rare and often severe genetic disorders that have been studied since the twentieth century. These progeroid syndromes are defined as segmental because only some of the features observed during natural aging are accelerated.Methods: Since 2015, the Molecular Genetics Laboratory in Marseille La Timone Hospital proposes molecular diagnosis of premature aging syndromes including laminopathies and related disorders upon NGS sequencing of a panel of 82 genes involved in these syndromes. We analyzed the results obtained in 4 years on 66 patients issued from France and abroad.Results: Globally, pathogenic or likely pathogenic variants (ACMG class 5 or 4) were identified in about 1/4 of the cases; among these, 9 pathogenic variants were novel. On the other hand, the diagnostic yield of our panel was over 60% when the patients were addressed upon a nosologically specific clinical suspicion, excepted for connective tissue disorders, for which clinical diagnosis may be more challenging. Prenatal testing was proposed to 3 families. We additionally detected 16 variants of uncertain significance and reclassified 3 of them as benign upon segregation analysis in first degree relatives.Conclusions: High throughput sequencing using the Laminopathies/ Premature Aging disorders panel allowed molecular diagnosis of rare disorders associated with premature aging features and genetic counseling for families, representing an interesting first-level analysis before whole genome sequencing may be proposed, as a future second step, by the National high throughput sequencing platforms ("Medicine France Genomics 2025" Plan), in families without molecular diagnosis. [ABSTRACT FROM AUTHOR]

Background: Riluzole has been reported to be beneficial in patients with cerebellar ataxia; however, effectiveness in individual subtypes of disease is unclear due to heterogeneity in participants' causes and stages of disease. Our aim was to test riluzole in a single genetic disease, spinocerebellar ataxia type 2.Methods: We did a randomised, double-blind, placebo-controlled, multicentre trial (the ATRIL study) at eight national reference centres for rare diseases in France that were part of the Neurogene National Reference Centre for Rare Diseases. Participants were patients with spinocerebellar ataxia type 2 with an age at disease onset of up to 50 years and a scale for the assessment and rating of ataxia (SARA) score of at least 5 and up to 26. Patients were randomly assigned centrally (1:1) to receive either riluzole 50 mg orally or placebo twice per day for 12 months. Two visits, at baseline and at 12 months, included clinical measures and 3T brain MRI. The primary endpoint was the proportion of patients whose SARA score improved by at least 1 point. Analyses were done in the intention-to-treat population (all participants who were randomly assigned) and were done with only the observed data (complete case analysis). This trial is registered at ClinicalTrials.gov (NCT03347344) and has been completed.Findings: Between Jan 18, 2018, and June 14, 2019, we enrolled 45 patients. 22 patients were randomly assigned to receive riluzole and 23 to receive placebo. Median age was 42 years (IQR 36-57) in the riluzole group and 49 years (40-56) in the placebo group and 23 (51%) participants were women. All participants presented with moderate-stage disease, characterised by a median SARA score of 13·5 (IQR 9·5-16·5). The primary endpoint, SARA score improvement of at least 1 point after 12 months, was observed in seven patients (32%) in the treated group versus nine patients (39%) in the placebo group, with a mean difference of -10·3% (95% CI -37·4% to 19·2%; p=0·75). SARA score showed a median increase (ie, worsening) of 0·5 points (IQR -1·5 to 1·5) in the riluzole group versus 0·3 points (-1·0 to 2·5) in the placebo group (p=0·70). No serious adverse event was reported in the riluzole-treated group whereas four patients in placebo group had a serious adverse event (hepatic enzyme increase, fracture of external malleolus, rectorrhagia, and depression). The number of patients with adverse events was similar in both groups (riluzole 16 [73%] patients vs placebo 19 [83%] patients; p=0·49).Interpretation: We were able to recruit 45 patients moderately affected by spinocerebellar ataxia type 2 for this trial. Riluzole did not improve clinical or radiological outcomes in these patients. However, our findings provide data on progression of spinocerebellar ataxia type 2 that might prove to be valuable for the design of other clinical trials.Funding: French Ministry of Health. [ABSTRACT FROM AUTHOR]

Examines autosomal dominant cerebellar ataxia (ADCA) and mental retardation in a large French family. Exhibition of mild developmental delays in motor acquisition; Display of moderate cerebellar and pontine atrophy; Evidence of linkage to chromosome 19q13.3-q13.4.

HNF1B-related disease is an emerging condition characterized by an autosomal-dominant inheritance, a 50% rate of de novo mutations, and a highly variable phenotype (renal involvement, maturity-onset diabetes of the young type 5, pancreatic hypoplasia, and urogenital tract and liver test abnormalities). Given the current lack of pathognomonic characteristics and the wide overlap with other conditions, a genetic test is the diagnostic gold standard. However, pre-genetic screening is mandatory because genetic testing has substantial costs. Our aim was to develop a HNF1B score, based on clinical, imaging, and biological variables, as a pivotal tool for rational genetic testing. A score was created using a weighted combination of the most discriminative characteristics based on the frequency and specificity in published series. The HNF1B score is calculated upon 17 items including antenatal discovery, family history, and organ involvement (kidney, pancreas, liver, and genital tract). The performance of the score was assessed by a ROC curve analysis in a 433-individual cohort containing 56 HNF1B cases. The HNF1B score efficiently and significantly discriminated between mutated and nonmutated cases (AUC 0.78). The optimal cutoff threshold for the negative predictive value to rule out HNF1B mutations in a suspected individual was 8 (sensitivity 98.2%, specificity 41.1%, and negative predictive value over 99%). Thus, the HNF1B score is a simple and accurate tool to provide a more rational approach to select patients for HNF1B screening.

Purpose: Inherited retinal dystrophies (IRDs) and inherited optic neuropathies (IONs) are rare diseases defined by specific clinical and molecular features. The relative prevalence of these conditions was determined in Southern France., Methods: Patients recruited from a specialized outpatient clinic over a 21-year period underwent extensive clinical investigations and 107 genes were screened by polymerase chain reaction/sequencing., Results: There were 1957 IRD cases (1481 families) distributed in 70% of pigmentary retinopathy cases (56% non-syndromic, 14% syndromic), 20% maculopathies and 7% stationary conditions. Patients with retinitis pigmentosa were the most frequent (47%) followed by Usher syndrome (10.8%). Among non-syndromic pigmentary retinopathy patients, 84% had rod-cone dystrophy, 8% cone-rod dystrophy and 5% Leber congenital amaurosis. Macular dystrophies were encountered in 398 cases (30% had Stargardt disease and 11% had Best disease). There were 184 ION cases (127 families) distributed in 51% with dominant optic neuropathies, 33% with recessive/sporadic forms and 16% with Leber hereditary optic neuropathy. Positive molecular results were obtained in 417/609 families with IRDs (68.5%) and in 27/58 with IONs (46.5%). The sequencing of 5 genes (ABCA4, USH2A, MYO7A, RPGR and PRPH2) provided a positive molecular result in 48% of 417 families with IRDs. Except for autosomal retinitis pigmentosa, in which less than half the families had positive molecular results, about 75% of families with other forms of retinal conditions had a positive molecular diagnosis., Conclusions: Although gene discovery considerably improved molecular diagnosis in many subgroups of IRDs and IONs, retinitis pigmentosa, accounting for almost half of IRDs, remains only partly molecularly defined.

Purpose: Myopia is a complex trait affected by both genetic and environmental factors. High myopia is associated with increased risk of sight threatening eye disorders such as retinal detachment. The purpose of this genome-wide association study was to identify susceptibility genes contributing to high myopia in the French population., Methods: High myopic cases were genotyped using Affymetrix SNP 6.0 chips and population controls were selected from the GABRIEL French dataset, in which samples were genotyped by Illumina Human610 quad array. The association study was conducted using 152,234 single nucleotide polymorphisms that were present on both manufacturers' chips in 192 high myopic cases and 1064 controls to identify associated regions. Imputation was performed on peak regions., Results: Associations were found at known myopia locus MYP10 on chromosome 8p23 and MYP15 on chromosome 10q21.1. Rs189798 (8p23), and rs10825992 (10q21.1) showed the strongest associations in these regions (P = 6.32 × 10(-7) and P = 2.17 × 10(-5), respectively). The imputed results at 8p23 showed two peaks of interest. The first spanned 30 kb including rs189798 between MIR4660 and PPP1R3B with the most significant association at rs17155227 (P = 1.07 × 10(-10)). The second novel peak was 4 kb in length, encompassing MIR124-1 and the MSRA gene, with the strongest association at rs55864141 (P = 1.30 × 10(-7)). The peak of imputed data at 10q21.1 was 70 kb in length between ZWINT and MIR3924, with rs3107503 having the lowest P value (P = 1.54 × 10(-7))., Conclusions: We provide evidence for the association of MYP10 at 8p23 and MYP15 at 10p21.1 with high myopia in the French population and refine these regions of association.

Purpose: We conducted a linkage analysis in high myopia families to replicate suggestive results from chromosome 7q36 using a model of autosomal dominant inheritance and genetic heterogeneity. We also performed a genome-wide scan to identify novel loci., Methods: Twenty-six families, with at least two high-myopic subjects (ie. refractive value in the less affected eye of -5 diopters) in each family, were included. Phenotypic examination included standard autorefractometry, ultrasonographic eye length measurement, and clinical confirmation of the non-syndromic character of the refractive disorder. Nine families were collected de novo including 136 available members of whom 34 were highly myopic subjects. Twenty new subjects were added in 5 of the 17 remaining families. A total of 233 subjects were submitted to a genome scan using ABI linkage mapping set LMSv2-MD-10, additional markers in all regions where preliminary LOD scores were greater than 1.5 were used. Multipoint parametric and non-parametric analyses were conducted with the software packages Genehunter 2.0 and Merlin 1.0.1. Two autosomal recessive, two autosomal dominant, and four autosomal additive models were used in the parametric linkage analyses., Results: No linkage was found using the subset of nine newly collected families. Study of the entire population of 26 families with a parametric model did not yield a significant LOD score (>3), even for the previously suggestive locus on 7q36. A non-parametric model demonstrated significant linkage to chromosome 7p15 in the entire population (Z-NPL=4.07, p=0.00002). The interval is 7.81 centiMorgans (cM) between markers D7S2458 and D7S2515., Conclusions: The significant interval reported here needs confirmation in other cohorts. Among possible susceptibility genes in the interval, certain candidates are likely to be involved in eye growth and development.

Pseudoxanthoma elasticum (PXE) is an autosomal recessive disorder of connective tissues, which manifests with cutaneous, ophthalmologic and cardiovascular findings. PXE is caused by mutations in ABCC6 encoding a multidrug resistance protein (ABCC6, also known as MRP6). ABCC6 mutation detection rate ranges from 55% to 97% and it has been suggested that some of the remaining unidentified mutant alleles could correspond to large genomic rearrangements. In our cohort of 65 French PXE patients analysed for ABCC6 mutations, we identified two novel homozygous ABCC6 exonic deletions (deletions of exons 9-10 and exons 24-27). In order to systematically search for heterozygous genomic rearrangements, we have developed a quantitative multiplex PCR of short fluorescent fragments (QMPSF) approach that screens the 31 exons of ABCC6. We used QMPSF to analyse 13 PXE carrying at least one unidentified mutant, corresponding to 18 unidentified mutated alleles. This led to the detection of three large ABCC6 deletions, and two deletions of a single exon (exon 1 and exon 21). Thus QMPSF identified the causative mutation in 28% (5/18) of the uncharacterized ABCC6 mutant alleles in this cohort., (Copyright 2007 Wiley-Liss, Inc.)