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Vilain C, Rens C, Aeby A, Balériaux D, Van Bogaert P, Remiche G, Smet J, Van Coster R, Abramowicz M, Pirson I. A novel NDUFV1 gene mutation in complex I deficiency in consanguineous siblings with brainstem lesions and Leigh syndrome. Although deficiency of complex I of the mitochondrial respiratory chain is a frequent cause of encephalopathy in children, only a few mutations have been reported in each of its subunits. In the absence of families large enough for conclusive segregation analysis and of robust functional testing, it is difficult to unequivocally show the causality of the observed mutations and to delineate genotype-phenotype correlations, making additional observations necessary. We observed two consanguineous siblings with an early-onset encephalopathy, medulla, brainstem and mesencephalon lesions on brain magnetic resonance imaging and death before 8 months of age, caused by a complex I deficiency. We used a homozygosity mapping approach and identified a missense mutation in the NDUFV1 gene. The mutation, p.Arg386His, affects a highly conserved residue, contiguous to a cysteine residue known to coordinate an Fe ion. This observation adds to our understanding of complex I deficiency disease. It validates the important role of Arg386 and therefore supports the current molecular model of iron-sulfur clusters in NDUFV1. [ABSTRACT FROM AUTHOR]

Purpose Hypohidrotic ectodermal dysplasia is usually transmitted as an X-linked recessive trait. This is a really rare condition with a prevalence of 1 for 100 000 births. Patients present a classical triad of hypotrichosis, anhydrosis or hypohydrosis and dental abnormalities. We report a 16 year old boy presenting a mild phenotype of HED and a hemeralopia due to a retinitis pigmentosa, without dysmorphia, intellectual deficiency or other associated feature. The parents were not consanguineous and the family history was unremarkable. Methods A full field ERG according the ISCEV protocol, a goldmann visual field, color and autofluorescent fundu's photographies were recorded. Results The scotopic responses were diminished bilaterally confirming the existence of a retinitis pigmentosa. Conclusions We report a patient with the association of HED and retinitis pigmentosa, a previously unreported association that might represent a novel genetic syndrome. [ABSTRACT FROM AUTHOR]

Nuclear Speckle Splicing Regulator Protein 1 (NSRP1) is a splice factor found in nuclear speckles, which are small membrane-free organelles implicated in epigenetic regulation, chromatin organization, DNA repair, and RNA modification. Bi-allelic loss-of-function variants in NSRP1 have recently been identified in patients suffering from a severe neurodevelopmental disorder, presenting with neurodevelopmental delay, epilepsy, microcephaly, hypotonia, and spastic cerebral palsy. Described patients acquired neither independent walking nor speech and often showed anomalies on cerebral MRI. Here we describe the case of a 14-year-old girl with motor and language delay as well as intellectual disability, who presents an ataxic gait but walks without assistance and speaks in short sentences. Whole-genome sequencing revealed the compound heterozygous NSRP1 variants c.114 + 2T > G and c.1595T > A (p.Val532Glu). Functional validation using HEK293T cells transfected with either wild-type or mutated GFP-tagged Nsrp1 suggests that the Val532Glu variant interferes with the function of the nuclear localization signal, and leads to mislocalization of NSRP1 in the cytosol, thus confirming the pathogenicity of the observed variant. This case helps to expand the phenotypic and genetic spectrum associated with pathogenic NSRP1 variants and indicates that this diagnosis should also be suspected in patients with milder phenotypes., (© 2024 Wiley Periodicals LLC.)

Autosomal dominant and recessive mutations in COL12A1 cause the Ehlers-Danlos/myopathy overlap syndrome. Here, we describe a boy with fetal hypokinesia, severe neonatal weakness, striking hyperlaxity, high arched palate, retrognathia, club feet, and pectus excavatum. His motor development was initially delayed but muscle strength improved with time while hyperlaxity remained very severe causing recurrent joint dislocations. Using trio exome sequencing and a copy number variation (CNV) analysis tool, we identified an in-frame de novo heterozygous deletion of the exons 45 to 54 in the COL12A1 gene. Collagen XII immunostaining on cultured skin fibroblasts demonstrated intracellular retention of collagen XII, supporting the pathogenicity of the deletion. The phenotype of our patient is slightly more severe than other cases with dominantly acting mutations, notably with the presence of fetal hypokinesia. This case highlights the importance of CNVs analysis in the COL12A1 gene in patients with a phenotype suggesting Ehlers-Danlos/myopathy overlap syndrome., (© 2022 Wiley Periodicals LLC.)

We report the case of an 11-year-old Syrian girl born to consanguineous parents, who presents an ataxic gait from early childhood. On clinical examination, she presented a severe static - kinetic cerebellar syndrome, walking without support is possible for short distances only. Strikingly, three consecutive MRIs did not show any sign of cerebellar abnormalities, but a brain positron emission tomography (PET) using [18F]-fluorodeoxyglucose (FDG) demonstrated a clear decrease in glucose metabolism in the cerebellum as well as the anterior and medial temporal lobe bilaterally. A clinical exome analysis identified a novel homozygous c.251A > G (p.Asn84Ser) likely pathogenic variant in the carbonic anhydrase 8 (CA8) gene. CA8 mutations cause cerebellar ataxia, mental retardation, and disequilibrium syndrome subtype 3 (CAMRQ3), a rare genetically autosomal recessive disorder, only described in four families, so far with the frequent observation of quadrupedal gait. The proband differed with other reported CA8 mutations by the absence of clear cerebellar signs on brain MRI and the presence of focal seizures. This report expands the clinical spectrum associated with mutations in CA8 and illustrates the possible discrepancy between (mild) neuro-radiological images (MRI) and (severe) clinical phenotype in young individuals. In contrast, the observation of clear cerebellar abnormal metabolic findings suggests that the FDG-PET scan may be used as an early marker for hereditary ataxia., (© 2020 Wiley Periodicals LLC.)

We report the case of a 7-year-old male of Western European origin presenting with moderate intellectual disability, severe childhood apraxia of speech in the presence of oral and manual dyspraxia, and hypotonia across motor systems including the oral and speech motor systems. Exome sequencing revealed a de novo frameshift protein truncating mutation in the fourth exon of BCL11A, a gene recently demonstrated as being involved in cognition and language development. Making parallels with a previously described patient with a 200 kb 2p15p16.1 deletion encompassing the entire BCL11A gene and displaying a similar phenotype, we characterize in depth how BCL11A is involved in clinical aspects of language development and oral praxis., (© 2017 The Authors. American Journal of Medical Genetics Part A Published by Wiley Periodicals, Inc.)

We report on five male subjects with a triad of signs compatible with Hartsfield syndrome: ectrodactyly, holoprosencephaly, and mental retardation. Only six patients with this distinctive association have been reported over the past 20 years, all of them being males. Of the patients described here, some have unreported findings such as vermian hypoplasia in one and prolonged survival into adulthood in two. Two patients developed central diabetes insipidus. All were mentally retarded. No abnormalities were found at the cytogenetic level, including array CGH in two. No known genes for holoprosencephaly or ectrodactyly were found, including GLI2. The cause of Hartsfield syndrome is unknown. An X-linked defect is possible, although no recurrences have been described to date. Our observations almost double the number of cases. They underscore the usefulness of fetal brain imaging in the differential diagnosis of syndromal clefting diagnosed in utero, particularly when ectrodactyly-ectodermal dysplasia-clefting syndrome is suspected.