Bi-Allelic Variants in MICU1 Cause Myopathy With Extrapyramidal Signs: Case Series, Phenotypic Spectrum, and Genotype-Phenotype Correlations From 61 Patients.

Myopathy with extrapyramidal signs (MPXPS) is a rare, autosomal-recessive, multisystem disorder caused by biallelic loss-of-function (LOF) variants in MICU1, the calcium-sensing gatekeeper of the mitochondrial calcium uniporter. We clinically and genetically characterized seven affected individuals from six Iranian-Turkish consanguineous families and combined these data with 54 previously published cases (total of 62). The targeted neuromuscular assessment, along with muscle biopsy and exome sequencing, identified six pathogenic MICU1 variants, including c.

Case Report of Pediatric HPCA-Associated Dystonia: Analysis of Ca and K Channel Dynamics and Experience With Pallidal Deep Brain Stimulation.

Background: Biallelic pathogenic variants in the HPCA gene cause HPCA-associated dystonia (DYT-HPCA), a rare autosomal recessive disorder characterized by generalized dystonia and complex motor symptoms. HPCA encodes hippocalcin, a Ca sensor that modulates neuronal activity through K channel activation. Here, we describe the clinical and molecular features of two children with novel HPCA variants and assess the impact of deep brain stimulation (DBS) (globus pallidus internus [Gpi]-DBS) on their movement disorders.

A programmed decline in ribosome levels governs human early neurodevelopment.

Many neurodevelopmental defects are linked to genes involved in housekeeping functions, such as those encoding ribosome biogenesis factors. How reductions in ribosome biogenesis can result in tissue- and developmental-specific defects remains unclear. Here we describe variants in the ribosome biogenesis factor AIRIM/C1orf109 that are primarily associated with neurodevelopmental disorders.

ELFN1 deficiency: The mechanistic basis and phenotypic spectrum of a neurodevelopmental disorder with epilepsy.

Purpose: Synaptic communication deficits are central to many neurodevelopmental disorders. However, for rare monogenic conditions, these disorders remain poorly defined, with limited understanding of their molecular etiology. A homozygous frameshift variant in the synaptic cell adhesion molecule ELFN1 was reported in a family with 3 affected siblings with epileptic encephalopathy, alongside a missense variant of uncertain significance in a cohort study involving a family with intellectual disability.

Deciphering DST-associated disorders: biallelic variants affecting DST-b cause a congenital myopathy.

Dystonin (DST) encodes three major isoforms, DST-a, DST-b, and DST-e. Biallelic pathogenic variants in DST have previously been associated with two allelic monogenic disorders: Hereditary Sensory and Autonomic Neuropathy type VI (caused by a loss of DST-a) and Epidermolysis bullosa simplex 3 (caused by a loss of DST-e). We investigated patients diagnosed with congenital myopathy using exome or genome sequencing.

Hyper IgE Syndromes: Understanding, Management, and Future Perspectives: A Narrative Review.

Background And Aim: Hyper IgE syndromes (HIES) are rare primary immunodeficiency characterized by susceptibility to specific infections, eczema, and elevated IgE levels. Pathogenic mutations in , , , , , , and have been identified as genetic factors contributing to phenotypes of HIES lead to hindered differentiation and activity, aberrant signaling cascades and disrupting immune regulation. HIES present a diverse clinical symptoms, challenging diagnosis and management; understanding its pathophysiology, genetics, and immunological abnormalities offer hope for improved outcomes.

Biallelic variants lead to a neurodevelopmental phenotype with gradual neurological impairment.

Biallelic variants in NADH (nicotinamide adenine dinucleotide (NAD) + hydrogen (H))-ubiquinone oxidoreductase 1 alpha subcomplex 13 have been linked to mitochondrial complex I deficiency, nuclear type 28, based on three affected individuals from two families. With only two families reported, the clinical and molecular spectrum of NADH-ubiquinone oxidoreductase 1 alpha subcomplex 13related diseases remains unclear. We report 10 additional affected individuals from nine independent families, identifying four missense variants (including recurrent c.

Human TRMT1 and TRMT1L paralogs ensure the proper modification state, stability, and function of tRNAs.

The tRNA methyltransferase 1 (TRMT1) enzyme catalyzes the N2,N2-dimethylguanosine (m2,2G) modification in tRNAs. Intriguingly, vertebrates encode an additional tRNA methyltransferase 1-like (TRMT1L) paralog. Here, we use a comprehensive tRNA sequencing approach to decipher targets of human TRMT1 and TRMT1L.

Normal very long-chain fatty acids level in a patient with peroxisome biogenesis disorders: a case report.

Background: Zellweger spectrum disorders (ZSDs) are a group of peroxisome biogenesis disorders (PBDs) with different variants in the PEX genes. The main biochemical marker for screening peroxisomal disorders is very long-chain fatty acids (VLCFAs). The study reveals a rare case of PBD in the Zellweger spectrum in which she had normal plasma VLCFA levels.

Epg5 links proteotoxic stress due to defective autophagic clearance and epileptogenesis in and Vici syndrome patients.

Epilepsy is a common neurological condition that arises from dysfunctional neuronal circuit control due to either acquired or innate disorders. Autophagy is an essential neuronal housekeeping mechanism, which causes severe proteotoxic stress when impaired. Autophagy impairment has been associated to epileptogenesis through a variety of molecular mechanisms.

Clinical and neuroradiological spectrum of biallelic variants in NOTCH3.

Background: NOTCH3 encodes a transmembrane receptor critical for vascular smooth muscle cell function. NOTCH3 variants are the leading cause of hereditary cerebral small vessel disease (SVD). While monoallelic cysteine-involving missense variants in NOTCH3 are well-studied in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), patients with biallelic variants in NOTCH3 are extremely rare and not well characterised.

Biallelic null variants in PNPLA8 cause microcephaly by reducing the number of basal radial glia.

Patatin-like phospholipase domain-containing lipase 8 (PNPLA8), one of the calcium-independent phospholipase A2 enzymes, is involved in various physiological processes through the maintenance of membrane phospholipids. Biallelic variants in PNPLA8 have been associated with a range of paediatric neurodegenerative disorders. However, the phenotypic spectrum, genotype-phenotype correlations and the underlying mechanisms are poorly understood.

Expanding the Clinical Phenotype of PLECTIN-Related Plectinopathies.

Background: Plectinopathy-associated disorders are caused by mutations in the gene encoding Plectin protein. mutations cause a spectrum of diseases defined by varying degrees of signs, mostly with epidermolysis bullosa simplex with muscular dystrophy (EBS-MD) and plectinopathy-related disorder is limb-girdle muscular dystrophy type 2Q (LGMD2Q). Here we report three cases with EBS-MD and LGMD2Q disorders analyzed by exome sequencing followed by mutation confirmation.

Evaluation of the Genetic Background of Patients with Niemann-Pick Disease.

Background: Congenital liver disease refers to a group of heterogeneous diseases from a clinical genetic point of view. The most crucial features are hepatosplenomegaly and elevated liver enzymes. This study aims to identify genetic variants causing the disease in three Iranian families with congenital liver disease using molecular techniques.

Brown-Vialetto-Van Laere syndrome.

Brown-Vialetto-Van Laere syndrome (BVVLS) is a rare neurodegenerative disorder of childhood. According to the previous reports, it has various primary signs and symptoms. Because of the simple treatment with riboflavin supplementation, it is important to have suspicious to this disease and begin treatment even before genetic test confirm.

Zebrafish as a model to investigate a biallelic gain-of-function variant in MSGN1, associated with a novel skeletal dysplasia syndrome.

Background/objectives: Rare genetic disorders causing specific congenital developmental abnormalities often manifest in single families. Investigation of disease-causing molecular features are most times lacking, although these investigations may open novel therapeutic options for patients. In this study, we aimed to identify the genetic cause in an Iranian patient with severe skeletal dysplasia and to model its molecular function in zebrafish embryos.

Biallelic variation in the choline and ethanolamine transporter underlies a pleiotropic disease spectrum from adult neurodegeneration to severe developmental disorders.

encodes Feline leukemia virus subgroup C receptor 1 (FLVCR1), a solute carrier (SLC) transporter within the Major Facilitator Superfamily. FLVCR1 is a widely expressed transmembrane protein with plasma membrane and mitochondrial isoforms implicated in heme, choline, and ethanolamine transport. While knockout mice die with skeletal malformations and defective erythropoiesis reminiscent of Diamond-Blackfan anemia, rare biallelic pathogenic variants are linked to childhood or adult-onset neurodegeneration of the retina, spinal cord, and peripheral nervous system.

A syndromic neurodevelopmental disorder caused by rare variants in PPFIA3.

PPFIA3 encodes the protein-tyrosine phosphatase, receptor-type, F-polypeptide-interacting-protein-alpha-3 (PPFIA3), which is a member of the LAR-protein-tyrosine phosphatase-interacting-protein (liprin) family involved in synapse formation and function, synaptic vesicle transport, and presynaptic active zone assembly. The protein structure and function are evolutionarily well conserved, but human diseases related to PPFIA3 dysfunction are not yet reported in OMIM. Here, we report 20 individuals with rare PPFIA3 variants (19 heterozygous and 1 compound heterozygous) presenting with developmental delay, intellectual disability, hypotonia, dysmorphisms, microcephaly or macrocephaly, autistic features, and epilepsy with reduced penetrance.

Bi-allelic genetic variants in the translational GTPases GTPBP1 and GTPBP2 cause a distinct identical neurodevelopmental syndrome.

The homologous genes GTPBP1 and GTPBP2 encode GTP-binding proteins 1 and 2, which are involved in ribosomal homeostasis. Pathogenic variants in GTPBP2 were recently shown to be an ultra-rare cause of neurodegenerative or neurodevelopmental disorders (NDDs). Until now, no human phenotype has been linked to GTPBP1.