24 research outputs found

    Sepsis by Capnocytophaga

    Get PDF
    Capnocytophaga species is a commensal gram-negative rod capnophilic facultative anaerobic bacterium that colonizes the oral cavity of humans and animals. This bacterium can cause severe illness in patients with alcohol addiction, chronic lung diseases, liver diseases and immunosuppression. Herein, we report a rare case of sepsis caused by C. sputigena in a 83-year-old woman

    Recessive mutations in MSTO1 cause mitochondrial dynamics impairment, leading to myopathy and ataxia.

    Get PDF
    We report here the first families carrying recessive variants in the MSTO1 gene: compound heterozygous mutations were identified in two sisters and in an unrelated singleton case, who presented a multisystem complex phenotype mainly characterized by myopathy and cerebellar ataxia. Human MSTO1 is a poorly studied protein, suggested to have mitochondrial localization and to regulate morphology and distribution of mitochondria. As for other mutations affecting genes involved in mitochondrial dynamics, no biochemical defects typical of mitochondrial disorders were reported. Studies in patients' fibroblasts revealed that MSTO1 protein levels were strongly reduced, the mitochondrial network was fragmented, and the fusion events among mitochondria were decreased, confirming the deleterious effect of the identified variants and the role of MSTO1 in modulating mitochondrial dynamics. We also found that MSTO1 is mainly a cytosolic protein. These findings indicate recessive mutations in MSTO1 as a new cause for inherited neuromuscular disorders with multisystem features.Contract grant sponsors: EU NeurOmics (project N. 2012‐305121‐2); the European Community's Seventh Framework Programme (FP7/2007‐2013); Regione Emilia Romagna; the Telethon (grant GGP15041); the Pierfranco and Luisa Mariani Foundation; the MRC‐QQR (2015‐20120); the ERC advanced grant (FP7‐322424); the NRJ‐Institut de France grant; Telethon Network of Genetic Biobanks (grant GTB12001J); MRC Neuromuscular Centre (for the Biobank); Muscular Dystrophy UK; National Institute for Health Research Biomedical Research Centre at Great Ormond Street Hospital for Children NHS Foundation Trust and University College London

    Identification of a deep intronic mutation in the COL6A2 gene by a novel custom oligonucleotide CGH array designed to explore allelic and genetic heterogeneity in collagen VI-related myopathies

    Get PDF
    BACKGROUND: Molecular characterization of collagen-VI related myopathies currently relies on standard sequencing, which yields a detection rate approximating 75-79% in Ullrich congenital muscular dystrophy (UCMD) and 60-65% in Bethlem myopathy (BM) patients as PCR-based techniques tend to miss gross genomic rearrangements as well as copy number variations (CNVs) in both the coding sequence and intronic regions. METHODS: We have designed a custom oligonucleotide CGH array in order to investigate the presence of CNVs in the coding and non-coding regions of COL6A1, A2, A3, A5 and A6 genes and a group of genes functionally related to collagen VI. A cohort of 12 patients with UCMD/BM negative at sequencing analysis and 2 subjects carrying a single COL6 mutation whose clinical phenotype was not explicable by inheritance were selected and the occurrence of allelic and genetic heterogeneity explored. RESULTS: A deletion within intron 1A of the COL6A2 gene, occurring in compound heterozygosity with a small deletion in exon 28, previously detected by routine sequencing, was identified in a BM patient. RNA studies showed monoallelic transcription of the COL6A2 gene, thus elucidating the functional effect of the intronic deletion. No pathogenic mutations were identified in the remaining analyzed patients, either within COL6A genes, or in genes functionally related to collagen VI. CONCLUSIONS: Our custom CGH array may represent a useful complementary diagnostic tool, especially in recessive forms of the disease, when only one mutant allele is detected by standard sequencing. The intronic deletion we identified represents the first example of a pure intronic mutation in COL6A genes

    Sepsis by Capnocytophaga

    Get PDF
    Capnocytophaga species is a commensal gram-negative rod capnophilic facultative anaerobic bacterium that colonizes the oral cavity of humans and animals. This bacterium can cause severe illness in patients with alcohol addiction, chronic lung diseases, liver diseases and immunosuppression. Herein, we report a rare case of sepsis caused by C. sputigena in a 83-year-old woman

    Co-Occurrence of Fragile X Syndrome with a Second Genetic Condition: Three Independent Cases of Double Diagnosis

    No full text
    Fragile X syndrome (FXS) is the most common form of inherited intellectual disability and autism caused by the instability of a CGG trinucleotide repeat in exon 1 of the FMR1 gene. The co-occurrence of FXS with other genetic disorders has only been occasionally reported. Here, we describe three independent cases of FXS co-segregation with three different genetic conditions, consisting of Duchenne muscular dystrophy (DMD), PPP2R5D--related neurodevelopmental disorder, and 2p25.3 deletion. The co-occurrence of DMD and FXS has been reported only once in a young boy, while in an independent family two affected boys were described, the elder diagnosed with FXS and the younger with DMD. This represents the second case in which both conditions coexist in a 5-year-old boy, inherited from his heterozygous mother. The next double diagnosis had never been reported before: through exome sequencing, a girl with FXS who was of 7 years of age with macrocephaly and severe psychomotor delay was found to carry a de novo variant in the PPP2R5D gene. Finally, a maternally inherited 2p25.3 deletion associated with a decreased level of the MYT1L transcript, only in the patient, was observed in a 33-year-old FXS male with severe seizures compared to his mother and two sex- and age-matched controls. All of these patients represent very rare instances of genetic conditions with clinical features that can be modified by FXS and vice versa

    Identification and characterization of novel collagen VI non-canonical splicing mutations causing Ullrich congenital muscular dystrophy

    No full text
    Splicing mutations occurring outside the invariant GT and AG dinucleotides are frequent in disease genes and the definition of their pathogenic potential is often challenging. We have identified four patients affected by Ullrich congenital muscular dystrophy and carrying unusual mutations of COL6 genes affecting RNA splicing. In three cases the mutations occurred in the COL6A2 gene and consisted of nucleotide substitutions within the degenerated sequences flanking the canonical dinucleotides. In the fourth case, a genomic deletion occurred which removed the exon8-intron8 junction of the COL6A1 gene. These mutations induced variable splicing phenotypes, consisting of exon skipping, intron retention and cryptic splice site activation/usage. A quantitative RNA assay revealed a reduced level of transcription of the mutated in-frame mRNA originating from a COL6A2 point mutation at intronic position +3. At variance, the transcription level of the mutated in-frame mRNA originating from a genomic deletion which removed the splicing sequences of COL6A1 exon 8 was normal. These findings suggest a different transcriptional efficiency of a regulatory splicing mutation compared to a genomic deletion causing a splicing defect

    Muscle MRI in Becker muscular dystrophy

    No full text
    The aim of this study was to evaluate pelvis and lower limb muscle MRI scans of 46 patients affected by Becker muscular dystrophy 15 (BMD) subdivided according to disease severity ranging from clinically asymptomatic patients to patients who had lost ambulation. 16 We found a distinct pattern on muscle imaging characterized by prominent involvement of the gluteus maximus and medius, adductor 17 magnus, biceps femoris long head, semimembranosus and vasti. This pattern was consistent in all the 25 symptomatic patients. Milder 18 changes in the same muscles were found in 13 of the 21 asymptomatic cases. The other 8 asymptomatic patients had a normal scan. The 19 severity of muscle involvement was significantly correlated with age. 20 Our results suggest that a distinct pattern of muscle involvement can be detected in BMD. The early identification of muscle changes 21 in a proportion of asymptomatic patients may be useful as an additional tool in the diagnostic workup

    Syndromic craniosynostosis can define new candidate genes for suture development or result from the non-specifc effects of pleiotropic genes: Rasopathies and chromatinopathies as examples

    No full text
    Craniosynostosis is a heterogeneous condition caused by the premature fusion of cranial sutures, occurring mostly as an isolated anomaly. Pathogenesis of non-syndromic forms of craniosynostosis is largely unknown. In about 15-30% of cases craniosynostosis occurs in association with other physical anomalies and it is referred to as syndromic craniosynostosis. Syndromic forms of craniosynostosis arise from mutations in genes belonging to the Fibroblast Growth Factor Receptor (FGFR) family and the interconnected molecular pathways in most cases. However it can occur in association with other gene variants and with a variety of chromosome abnormalities as well, usually in association with intellectual disability (ID) and additional physical anomalies. Evaluating the molecular properties of the genes undergoing intragenic mutations or copy number variations (CNVs) along with prevalence of craniosynostosis in different conditions and animal models if available, we made an attempt to define two distinct groups of unusual syndromic craniosynostosis, which can reflect direct effects of emerging new candidate genes with roles in suture homeostasis or a non-specific phenotypic manifestation of pleiotropic genes, respectively. RASopathies and 9p23p22.3 deletions are reviewed as examples of conditions in the first group. In particular, we found that craniosynostosis is a relatively common component manifestation of cardio-facio-cutaneous (CFC) syndrome. Chromatinopathies and neurocristopathies are presented as examples of conditions in the second group. We observed that craniosynostosis is uncommon on average in these conditions. It was randomly associated with Kabuki, Koolen-de Vries/KANSL1 haploinsufficiency and Mowat-Wilson syndromes and in KAT6B-related disorders. As an exception, trigonocephaly in Bohring-Opitz syndrome reflects specific molecular properties of the chromatin modifier ASXL1 gene. Surveillance for craniosynostosis in syndromic forms of intellectual disability, as well as ascertainment of genomic CNVs by array-CGH in apparently non-syndromic craniosynostosis is recommended, to allow for improvement of both the clinical outcome of patients and the accurate individual diagnosis

    Upper Girdle Imaging in Facioscapulohumeral Muscular Dystrophy

    No full text
    Background: In Facioscapulohumeral muscular dystrophy (FSHD), the upper girdle is early involved and often difficult to assess only relying on physical examination. Our aim was to evaluate the pattern and degree of involvement of upper girdle muscles in FSHD compared with other muscle diseases with scapular girdle impairment. Methods: We propose an MRI protocol evaluating neck and upper girdle muscles. One hundred-eight consecutive symptomatic FSHD patients and 45 patients affected by muscular dystrophies and myopathies with prominent upper girdle involvement underwent this protocol. Acquired scans were retrospectively analyzed. Results: The trapezius (100% of the patients) and serratus anterior (85% of the patients) were the most and earliest affected muscles in FSHD, followed by the latissimus dorsi and pectoralis major, whilst spinati and subscapularis (involved in less than 4% of the patients) were consistently spared even in late disease stages. Asymmetry and hyperintensities on short-tau inversion recovery (STIR) sequences were common features, and STIR hyperintensities could also be found in muscles not showing signs of fatty replacement. The overall involvement appears to be disease-specific in FSHD as it significantly differed from that encountered in the other myopathies. Conclusions: The detailed knowledge of single muscle involvement provides useful information for correctly evaluating patients\u2019 motor function and to set a baseline for natural history studies. Upper girdle imaging can also be used as an additional tool helpful in supporting the diagnosis of FSHD in unclear situations, and may contribute with hints on the currently largely unknown molecular pathogenesis of this disease
    corecore