Recurrent familial case of early childhood sudden death: Complex post mortem genetic investigations.

Introduction: Sudden Unexplained Death in Childhood (SUDC) needs to be fully assessed considering its impact on the family, parents and siblings. Inborn Errors of Metabolism (IEM) such as Medium-Chain Acyl-CoA Dehydrogenase Deficiency (MCADD) should be taken into consideration when SUDC occurres. Our aim is to present a family with two successive SUDC and to discuss the post-mortem genetics investigations revealing an IEM implication.

Rare Missense Variants in KCNJ10 Are Associated with Paroxysmal Kinesigenic Dyskinesia.

Background: Although the group of paroxysmal kinesigenic dyskinesia (PKD) genes is expanding, the molecular cause remains elusive in more than 50% of cases.

Objective: The aim is to identify the missing genetic causes of PKD.

Methods: Phenotypic characterization, whole exome sequencing and association test were performed among 53 PKD cases.

Does Spinocerebellar ataxia 27B mimic cerebellar multiple system atrophy?

Background: Whether spinocerebellar ataxia 27B (SCA27B) may present as a cerebellar multiple system atrophy (MSA-C) mimic remains undetermined.

Objectives: To assess the prevalence of FGF14 (GAA) expansions in patients with MSA-C, to compare SCA27B and MSA-C clinical presentation and natural history.

Methods: FGF14 expansion screening combined with longitudinal deep-phenotyping in a prospective cohort of 195 patients with sporadic late-onset cerebellar ataxia.

Functional analysis of novel variants identified in cis in the PCCB gene in a patient with propionic acidemia.

Next-generation sequencing has improved the diagnosis of inborn errors of metabolism, allowing rapid confirmation of cases detected by clinical/biochemical studies or newborn screening. The challenge, however, remains for establishing the pathogenicity of the identified variants, especially for novel missense changes or small in-frame deletions. In this work we report a propionic acidemia patient exhibiting a severe neonatal form with coma and hyperammonaemia.

Natural History and Phenotypic Spectrum of GAA-FGF14 Sporadic Late-Onset Cerebellar Ataxia (SCA27B).

Background: Heterozygous GAA expansions in the FGF14 gene have been related to autosomal dominant cerebellar ataxia (SCA27B-MIM:620174). Whether they represent a common cause of sporadic late-onset cerebellar ataxia (SLOCA) remains to be established.

Objectives: To estimate the prevalence, characterize the phenotypic spectrum, identify discriminative features, and model longitudinal progression of SCA27B in a prospective cohort of SLOCA patients.

Recessive NUP54 Variants Underlie Early-Onset Dystonia with Striatal Lesions.

Infantile striatonigral degeneration is caused by a homozygous variant of the nuclear-pore complex (NPC) gene NUP62, involved in nucleo-cytoplasmic trafficking. By querying sequencing-datasets of patients with dystonia and/or Leigh(-like) syndromes, we identified 3 unrelated individuals with biallelic variants in NUP54. All variants clustered in the C-terminal protein region that interacts with NUP62.

Highlighting the Dystonic Phenotype Related to GNAO1.

Background: Most reported patients carrying GNAO1 mutations showed a severe phenotype characterized by early-onset epileptic encephalopathy and/or chorea.

Objective: The aim was to characterize the clinical and genetic features of patients with mild GNAO1-related phenotype with prominent movement disorders.

Methods: We included patients diagnosed with GNAO1-related movement disorders of delayed onset (>2 years).

Statistical Approach of the Role of the Conserved CSB-PiggyBac Transposase Fusion Protein (CSB-PGBD3) in Genotype-Phenotype Correlation in Cockayne Syndrome Type B.

Cockayne syndrome is a rare condition that encompasses a very wide spectrum of clinical severity. Mutations upstream of a transposon called PiggyBac Transposable Element Derived 3 in intron 5 of the gene could bring about less severe forms than mutations located downstream of that transposon insertion. Our aim was to study genotype-phenotype correlation by determining whether the position of each mutation of the gene has an impact on the phenotype.

Heterogeneous clinical features in Cockayne syndrome patients and siblings carrying the same CSA mutations.

Background: Cockayne syndrome (CS) is a rare autosomal recessive disorder caused by mutations in ERCC6/CSB or ERCC8/CSA that participate in the transcription-coupled nucleotide excision repair (TC-NER) of UV-induced DNA damage. CS patients display a large heterogeneity of clinical symptoms and severities, the reason of which is not fully understood, and that cannot be anticipated in the diagnostic phase. In addition, little data is available for affected siblings, and this disease is largely undiagnosed in North Africa.

Identification and Characterization of a Novel Recurrent Variant in Patients with a Severe Form of Cockayne Syndrome B.

Cockayne syndrome (CS) is a rare disease caused by mutations in / or /. We report here the clinical, genetic, and functional analyses of three unrelated patients mutated in / with a severe phenotype. After clinical examination, two patients were investigated via next generation sequencing, targeting seventeen Nucleotide Excision Repair (NER) genes.

Clinical and Mutation Spectra of Cockayne Syndrome in India.

Background: Cockayne syndrome is an autosomal recessive disorder caused by biallelic mutations in ERCC6 or ERCC8 genes.

Aims: To study the clinical and mutation spectrum of Cockayne syndrome.

Setting And Design: Medical Genetics Outpatient Department of Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow.

Expanding the clinical spectrum of STIP1 homology and U-box containing protein 1-associated ataxia.

Background: STUB1 has been first associated with autosomal recessive (SCAR16, MIM# 615768) and later with dominant forms of ataxia (SCA48, MIM# 618093). Pathogenic variations in STUB1 are now considered a frequent cause of cerebellar ataxia.

Objective: We aimed to improve the clinical, radiological, and molecular delineation of SCAR16 and SCA48.

Growth charts in Cockayne syndrome type 1 and type 2.

Cockayne syndrome (CS) is a multisystem degenerative disorder divided in 3 overlapping subtypes, with a continuous phenotypic spectrum: CS2 being the most severe form, CS1 the classical form and CS3 the late-onset form. Failure to thrive and growth difficulties are among the most consistent features of CS, leaving affected individuals vulnerable to numerous medical complications, including adverse effects of undernutrition, abrupt overhydration and overfeeding. There is thus a significant need for specific growth charts.

Early-onset nucleotide excision repair disorders with neurological impairment: Clues for early diagnosis and prognostic counseling.

Nucleotide excision repair associated diseases comprise overlapping phenotypes and a wide range of outcomes. The early stages still remain under-investigated and underdiagnosed, even although an early recognition of the first symptoms is of utmost importance for appropriate care and genetic counseling. We systematically collected clinical and molecular data from the literature and from newly diagnosed NER patients with neurological impairment, presenting clinical symptoms before the age of 12 months, including foetal cases.

Prenatal diagnosis of cerebro-oculo-facio-skeletal syndrome: Report of three fetuses and review of the literature.

Cerebro-oculo-facio-skeletal syndrome (COFS) is a rare autosomal recessive neurodegenerative disease belonging to the family of DNA repair disorders, characterized by microcephaly, congenital cataracts, facial dysmorphism and arthrogryposis. Here, we describe the detailed morphological and microscopic phenotype of three fetuses from two families harboring ERCC5/XPG likely pathogenic variants, and review the five previously reported fetal cases. In addition to the classical features of COFS, the fetuses display thymus hyperplasia, splenomegaly and increased hematopoiesis.

Defective transcription of ATF3 responsive genes, a marker for Cockayne Syndrome.

Cockayne syndrome (CS) is a rare genetic disorder caused by mutations (dysfunction) in CSA and CSB. CS patients exhibit mild photosensitivity and severe neurological problems. Currently, CS diagnosis is based on the inefficiency of CS cells to recover RNA synthesis upon genotoxic (UV) stress.

A severe case of Frank-ter Haar syndrome and literature review: Further delineation of the phenotypical spectrum.

Frank-ter Haar syndrome (FTHS) is a rare autosomal recessive syndrome resulting from mutations in the SH3PXD2B gene involved in the formation of podosomes and invadopodia which have a role in extracellular matrix remodelling and cell migration. FTHS is characterized by facial dysmorphism, megalocornea, inconstant glaucoma, variable developmental delay, skeletal and cardiac anomalies. To date, 40 patients have been reported in the literature with a clinical diagnosis of FTHS, only 20 patients having identified mutations.

Renal disease in Cockayne syndrome.

Background: Cockayne Syndrome (CS) is a rare autosomal recessive multi-systemic disorder, characterized; by developmental delay, microcephaly, severe growth failure and sensorial impairment. Renal complications have been reported but remain underinvestigated. The objective of this study was to perform a review of renal disease in a cohort of CS patients.

Functional and clinical relevance of novel mutations in a large cohort of patients with Cockayne syndrome.

Background: Cockayne syndrome (CS) is a rare, autosomal recessive multisystem disorder characterised by prenatal or postnatal growth failure, progressive neurological dysfunction, ocular and skeletal abnormalities and premature ageing. About half of the patients with symptoms diagnostic for CS show cutaneous photosensitivity and an abnormal cellular response to UV light due to mutations in either the / or / gene. Studies performed thus far have failed to delineate clear genotype-phenotype relationships.

Deep intronic variation in splicing regulatory element of the ERCC8 gene associated with severe but long-term survival Cockayne syndrome.

Cockayne syndrome is an autosomal recessive multisystem disorder characterized by intellectual disability, microcephaly, severe growth failure, sensory impairment, peripheral neuropathy, and cutaneous sensitivity. This rare disease is linked to disease-causing variations in the ERCC6 (CSB) and ERCC8 (CSA) genes. Various degrees of severity have been described according to age at onset and survival, without any clear genotype-phenotype correlation.

Affected female carriers of MTM1 mutations display a wide spectrum of clinical and pathological involvement: delineating diagnostic clues.

X-linked myotubular myopathy (XLMTM), a severe congenital myopathy, is caused by mutations in the MTM1 gene located on the X chromosome. A majority of affected males die in the early postnatal period, whereas female carriers are believed to be usually asymptomatic. Nevertheless, several affected females have been reported.